The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Guns, Politics, Gunsmithing & Reloading Reloading Have you ever had dramatic changes in accuracy with .2 of a grain upd infoGo | New | Find | Notify | Tools | Reply | |
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So I have a Rem 700 in 308 win that has been accurrized. Its an honest 1/2 MOA gun for 3 shots with tuned match loads. I decide to try some Hornady GMXs (in case I take it hunting) they are also accurate in my Kimber. I made 7 different loads starting from 44.6 thru 45.8 grains of varget in .2 grain increments. From 44.6 thru 45.4 its all 1.5-2 inch groups and no real pattern of contraction or expansion. At 45.6, bingo 1/2 inch groups but back to 1.5 inches at 45.8 I decide what the heck let me fire off 3 quick rounds of my 173grn Lake City Match Bullets which is another accurate bullet for the rifle and a 1/2 inch group. I have just never seen such a dramatic change. I have heard about it ...but never seen a rifle go from barely acceptable to tack driver with 2/10 of a change in charge weight for a given bullet. Any thoughts Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue.  What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | ||
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Nothing that was not a fluke. Every time I retry something like that it cannot be repeated. | |||
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[Have you ever had dramatic change in accuracy with .2 of a grain?] Yes. My dad-in-law's 140-grain SIERRA FB load for 7mm Rem Mag is specifically 66.8 grains RL-19. I tried it in a newly rebarreled lefty Lazermark and it clocked 3000 fps in a small group of five, just as it did in a lefty Remington laminated stock rifle sold to a surviving lease member. (I worked it up/shot it for him prior to his passing last year, about the time that you kindly bought some components. He'd loaded them in .2 grain increments.) Cheers! Barry _______________________ | |||
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My Frontier in .243 is that way...it will go from a under MOA group to a 2" group with an extra .2 from my best load....it's odd but it does happen. | |||
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How does that compare with being on the node. I understood that finding the right node was also the one that gave good accuracy slightly either side of the node as well. Just a thought-question. Von Gruff. | |||
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The issue of the node is the reason for the psot. I load for many rifles and I typically see a very consistent contraction and expansion...this was very dramatic everything at about 1.5 then boom .5 and then right back out. Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue. What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | |||
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My thought would be to load it again and confirm! Best to ya! Good shootin. | |||
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that is definitely part of the plan Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue. What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | |||
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Nope.....not that I can recall....and especially if one was to repeat it! /////////////////////////////////////////////////////////////////////////// "Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery." Winston Churchill | |||
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I work up in 1 grn increments so I know I haven’t ________________________________________________ Maker of The Frankenstud Sling Keeper Proudly made in the USA Acepting all forms of payment | |||
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everybody is a comedian...  Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue. What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | |||
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Those who can't, blab. I just finished load development with the creedmoor at 600 yards. 41 grains H-4350, 41.2, 41.4, 41.6. The first 3 had at least 4" of vertical dispersion for 5 shots. 41.6 had 2". I didn't go to 41.8 or 42 so I don't know how tolerant the barrel is to an increase in charge. | |||
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Mike - I suppose it is possible, but I have never seen it myself. My 700 PSS will reliably put both 168 grain Sierra Matchkings and 168 grain McCrackens into five shot groups which vary from 1/4 MOA to 1/2 MOA depending on my how my day is going...both my ability to shoot and my luck vary on any given day. The only accurizing done to my rifle was shortening the barrel to get rid of the threads someone had put on the muzzle end to use it with a "can" or a brake. I did the cutting off myself, and recrowned it. But those are not hunting bullets, so that's just an observation. I haven't even tried the same weight of Game Kings in it, let alone any of the newer bullets. It does that with the old "hi-power" competitors' formula...WW LRP, IMR 4895, and bullets seated .010" to .015" off the lands. I've stuck with 4895 for many of my medium powder capacity cartridge rifles, because it is very forgiving. My rifle will deliver that kind of accuracy from the bench with anywhere from 39.5 grains to 41.5 grains of any make of 4895. My country gal's just a moonshiner's daughter, but I love her still. | |||
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More testing is needed. | |||
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This 'inconsistency' is what I have been complaining about for years, with Hodgdon's 4895...very slight variations in charge and it can start throwing bullets all over the place.. IMR's version doesn't! That is the very reason Hodgdon's 4895 is about my least favorite powder...you can develop a load that is a tack driver, and change the charge even 1/10th of a grain and it will start throwing them all over the place.. personally I'd just change powders... for consistency that is why I prefer IMR powders over Hodgdon's ... however there are some good Hodgdon powders that are consistent.. H322, Varget, H 1000, 4831SC come to mind right off...( I am speaking of Hodgdon powders made by ADI)... | |||
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Just to pick a nit, I'm sure it would have something to do with the percentage of the overall load. .2grs in a small case, ie .222 or a Hornet might be significant, less so in a .308, and I can't see how it could affect a say .300WM. While I've never gotten any sort of straight line increase or decrease in accuracy when going up or down a powder sequence, I haven't gotten that dramatic a change in working up a load either. Even with the small cases. As posted, more groups need to be fired. Perhaps more shots per group. Aim for the exit hole | |||
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Tho I don't have a .308, I'd say it was a fluke. A 0.2 gr. change in powder charge for a .308 is miniscule. I think you'd be hard put to even see a change of velocity with your chrono. As another poster wrote, in a .222? Then I'd say "Ok, maybe". My previous .270 WSM literally shot a 5 shot group with all of them touching. This was when I was trying to work up a consistantly accurate load for it. I could never, ever repeat that group nor come close. I even had the seating depth down to a gnat's eye. BTW, that rifle hit the bricks south. Shooting a number of groups with that load to confirm or not would be my advice. Good luck. Bear in Fairbanks Unless you're the lead dog, the scenery never changes. I never thought that I'd live to see a President worse than Jimmy Carter. Well, I have. Gun control means using two hands. | |||
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When I asked about the node, I guess I should have been a bit more specific. I have read of more than one node and I was wondering if there was variables in the length of the node depending on where in the pressure-velocity range it fell. I havent personally loaded 308 but my 7x57 is not a million miles away and I did find some of the bullets had a shorter node than others and because the pressure-velocity can change depending on other factors I have been inclined to go with the longest node all other things ( bullet structural preformance ) being equal. Havent struck one as short as .2 yet though. Von Gruff. | |||
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In my rifles 2/10ths up or 2/10ths down makes very little difference in group size. If all other things are equal and secure, it's more of a "what condition the barrel is in" at the time each shot is fired than anything else. A good barrel will foul consistantly shot after shot. A bad barrel won't. That's just my observation with my rifles. I'm sure there has to be a exception out there somewhere and I hope you have it. "The right to bear arms" insures your right to freedom, free speech, religion, your choice of doctors, etc. ....etc. ....etc.... -----------------------------------one trillion seconds = 31,709 years------------------- | |||
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Can't what? You have my attention. ________________________________________________ Maker of The Frankenstud Sling Keeper Proudly made in the USA Acepting all forms of payment | |||
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Most powders have about 1/8 the specific gravity of brass. A variation of .2 gr powder charge is a volume change similar to a volume change equivalent to 1.6 grains in the weight of your cartridge cases. Does anyone here manage to keep their cases sorted to +/-.8 gr? I sure don't. | |||
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A very pregnant thought...perhaps it will give birth to mass thinking over of why our predecessors relied on multiple 10-shot groups to give them a truer indication of a rifle's accuracy. They considered 5-shot groups to be so greatly influenced by luck as to be relatively worthless for testing firearms and loads (or shooters). Many Schuetzenfests still include a 100-shot match, as a real test of who is the best shooter with the best rifle. One hundred shots for score, offhand, unlimited sighters, time limit one day. You'll really find out how dependable your rifle and load is (and you are) in that match. My country gal's just a moonshiner's daughter, but I love her still. | |||
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Perhaps some of you would like to fertilize these thoughts further? (sorry, I just couldn't help it) What exactly constitutes a group in everyones eyes?????? M-16 full auto or 10 rounds fired in rapid succession from a bolt rifle on a 105 F. degree day? Or should one wait until the barrel cools completely between shots? What about range conditions? How many shots in how long of time span with I suppose the exact same componants fired under the exact same conditions? And at what yardage? We have a local Schuetzenverein in our area, which I should be member of but I am not.I will talk to some of the board as I know a few, and see if they, (the local verein) still do the same as you said others do. "The right to bear arms" insures your right to freedom, free speech, religion, your choice of doctors, etc. ....etc. ....etc.... -----------------------------------one trillion seconds = 31,709 years------------------- | |||
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I know the yardage and the target may vary from locale to locale. I believe the old timers liked the 25-ring German target, and a range of 40 rods (220 yards) but things have been getting easier over the years in some areas.... Just look at the number of three shot "groups" people brag about. Lots easier to get a wallet "bragging" target with 3 shots than with 10, or 100! My country gal's just a moonshiner's daughter, but I love her still. | |||
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How true! For me personally, I consider a rifle a good shooter (and a good load) if both will duplicate a 3 shot group several times in succession (not always in the same day) with the same load before becoming fouled out. So I suppose it could be said I am shooting a 9 shot or 15 shot or whatever group. Having said that I consider a "one" shot group to be the most important on all of my huntingn rifles. In other words where the first shot hits on a cooled off barrel to simulate hunting conditions. The second shot being close to the first is nice to have also in case things go bad with the first and then a third shot close to the second is good in case the first two don't find their mark but then a fourth shot close to the third in case the first three don't......... "The right to bear arms" insures your right to freedom, free speech, religion, your choice of doctors, etc. ....etc. ....etc.... -----------------------------------one trillion seconds = 31,709 years------------------- | |||
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How did it work with the sighters? What was to stop you converting the hundred best shots of the day I mean? It sound like a grueling concept, do people do it any more? | |||
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Mike, on a serious note, I have a rifle that will do what you describe with OAL. At 3.60 it shoots 1/4-1/2" groups. At 3.995 it shoots 1 1/2" groups. I repeated this with seperate tests on two different day. I usually test in wider increments, but my 22-250 with W760 acts somewhat similar. 38gr 3/4" groups 38.5 3/16" groups 39 3/4" groups. I would be curious to see how that load performs across different temperatures. I'd be worried that small differences in other uncontrolable factors could turn it back into a 1 1/2" load on any given day. | |||
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Mike, .2 gr? Depending upon the powder scale; +/- .1 gr accuracy, could the spread be larger than .2 gr? Possibly .3 gr? Then I could see a difference. I wonder if the accuracy node is too small to keep using the same powder. Might be difficult to keep it within the same accuracy node depending upon weather, loading techniques, component consistency. Just a thought! Now, if you have an Acculab VIC 123 or something as accurate that measure +/- two 100th of a grain.......? Alan  | |||
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I work up loads in .2 increments as well. I've had many a rifle go from 1/2 to the 3/4 of just under MOA but nothing like you had. A full inch with the only change being .2 +/- powder is a lot. And the ones that have bounced around a bit are thinner profilies. Never had it happen to me on a H-bar tube. | |||
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The sighters are fired on a different target, and can be fired from any position, including the bench. Bench shooting of sighters wouldn't be very useful, I suspect, for a person whose record shots were going to be fired offhand, but if he/she wanted to do it, they could. As to "Do they do it anymore?" Well, by "any more",I have to say I don't know about the last couple of years. It was done as recently as into the 2000s for sure, at the Emerald Empire Schuetzenfest held at the Monroe, Oregon range (near Eugene/Springfield). When I expressed awe at the # of shots, The Match Director for the Schuetzenfest, Chauncey Roe, told me it was a commonly accepted match in Schuetzen type competition. I know Idaho Sharpshooter competed in it in the late 1990s. That Schuetzenfest was often held in consort with the registered CBA Memorial Match (held on the two days of the Memorial Day weekend, IIRC). A lot of the same shooters entered both. They were held on two different ranges at the same facility, but the firing points for the two sets of matches were only about 200-300 yards apart. | |||
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Trying to stay back on topic... Of course more groups need to be fired...I know that. What I found interesting is how this group occurred... My protocol is to start with a clean bbl and fire two fowling shots then work forward then backward through the loads to reduce the impact of "fowling and heat" on any one load. So since this was the 6th load it means that this 3 shot group represented the 6th, 9th, and 30th rounds fired. I think the above removes some of the "shooter variable" I am going to the range again and I am going to load some round on each side of this load and see what happens. Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue. What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | |||
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if you run the ammo over a chronograph you will see what the 0.2gr means. Some rifles are more sensitive to velocity nodes than others. I've had accuracy go to hell because of temperature changes that moved me out of a velocity node. 0.2gr can mean something in a smaller case as you approach higher levels. How much did 0.2gr move the velocity? Also at some loads the ES opens up a lot. Generally though that's as you get near max. This is in my potentially limited experience. I agree that one test proves little unless you are lucky. How often have you tested loads to find that this week's best is next week's second or third best etc. | |||
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 Anomaly? Probably I rebarreled to a 338RUM before I had a chance to retest ____________________________________ There are those who would misteach us that to stick in a rut is consistency - and a virtue, and that to climb out of the rut is inconsistency - and a vice. - Mark Twain | Chinese Proverb: When someone shares something of value with you and you benefit from it, you have a moral obligation to share it with others. ___________________________________ | |||
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well...it looks like it is holding somewhat true 45.4 3 three shot groups, average group size 1.55 45.6 3 three shot groups, average group size .680 45.8 3 three shot groups, average group size 1.30 Mike Legistine actu quod scripsi? Never under estimate the internet community's ability to reply to your post with their personal rant about their tangentially related, single occurrence issue. What I have learned on AR, since 2001: 1. The proper answer to: Where is the best place in town to get a steak dinner? is…You should go to Mel's Diner and get the fried chicken. 2. Big game animals can tell the difference between .015 of an inch in diameter, 15 grains of bullet weight, and 150 fps. 3. There is a difference in the performance of two identical projectiles launched at the same velocity if they came from different cartridges. 4. While a double rifle is the perfect DGR, every 375HH bolt gun needs to be modified to carry at least 5 down. 5. While a floor plate and detachable box magazine both use a mechanical latch, only the floor plate latch is reliable. Disregard the fact that every modern military rifle uses a detachable box magazine. 6. The Remington 700 is unreliable regardless of the fact it is the basis of the USMC M40 sniper rifle for 40+ years with no changes to the receiver or extractor and is the choice of more military and law enforcement sniper units than any other rifle. 7. PF actions are not suitable for a DGR and it is irrelevant that the M1, M14, M16, & AK47 which were designed for hunting men that can shoot back are all PF actions. 8. 95 deg F in Africa is different than 95 deg F in TX or CA and that is why you must worry about ammunition temperature in Africa (even though most safaris take place in winter) but not in TX or in CA. 9. The size of a ding in a gun's finish doesn't matter, what matters is whether it’s a safe ding or not. 10. 1 in a row is a trend, 2 in a row is statistically significant, and 3 in a row is an irrefutable fact. 11. Never buy a WSM or RCM cartridge for a safari rifle or your go to rifle in the USA because if they lose your ammo you can't find replacement ammo but don't worry 280 Rem, 338-06, 35 Whelen, and all Weatherby cartridges abound in Africa and back country stores. 12. A well hit animal can run 75 yds. in the open and suddenly drop with no initial blood trail, but the one I shot from 200 yds. away that ran 10 yds. and disappeared into a thicket and was not found was lost because the bullet penciled thru. I am 100% certain of this even though I have no physical evidence. 13. A 300 Win Mag is a 500 yard elk cartridge but a 308 Win is not a 300 yard elk cartridge even though the same bullet is travelling at the same velocity at those respective distances. | |||
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What effect a certain amount of powder OR difference in seating depth depends on WHAT size the cases are...HOW equal the cases are in case volume...how ACCURATE the powder is measured by weight or volume and a bunch of other factors to boot.... ANY change in powder amount relative to case volume will cause a change in velocity which also causes a change in the barrel harmonics which means the bullet exits the muzzle at a different point in the vibration each time. When you hit that null point or node then you get those bug holers because the barrel ISN'T moving when the bullet exits. That's where a "barrel tuner" comes in handy...just a tiny amount of pressure can change the muzzle node from spitting bullets everywhere to producing those bragging targets. I guarantee .2 difference in powder weight in a FB case will cause a difference in group size and the same goes for a 222/223 size case, but as you get into larger and larger volume cases the effect may or maynot drop off. I have/had several rifles that can see .1 difference in group sizes, but NOT at 100 yrds always...you need to get out there a bit farther to be see the change. On an exceptional barrel and load combination it will be well beyond 300 yds. A good chrono will show up the difference also but you need 10 shot groups or more for the average to settle down...a total waste of components for anything other than a benchrester or long ranger. You also have to periodically, no set amount of shots, adjust your seating AND powder amounts to keep in the sweet spot. My 17 to 6mm hotties can go from nailing anything I can get a scope on to barely hitting the ground in 200 rounds or less depending on the "heat" of the cartridge...my 22-243 and 6mm-284 get a tune up every 100 rounds or so. I keep telling everyone to check out the reloading section here on AR as it gives velocities, powders and amounts AND group sizes...the information presented should be self evident and an excellent way to come up with load data. Luck | |||
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Mike I just had the same thing happen when testing loads for my Ruger No.1 in 7x57. 1.3-1.5" inch groups for 45.0, 45.5 and 46.0 gr, except for the 45.7 gr load which was a one holer (0.173"CTC). These three shots were shots #3,6, and #9 fired that day. | |||
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| One of Us |
I once had a 17Rem that was a PIA to load for. .1gr increments could make the difference in great groups with normal pressure signs and scattered groups and blown primers/Xtremely hard extraction. I promptly sold it and never looked back. We Band of Bubbas N.R.A Life Member TDR Cummins Power All The Way Certified member of the Whompers Club | |||
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And one of the most important "other factors" is how close to the upper edge of the powder's designed pressure envelope one is loading. Of course that varies by rifle, even in the same chambering with the same components. There does become a point with every powder which burns fast enough to make overloads possible, where the pressure curve quits curving upward and goes pretty much straight up. An added .1 grain change there can be a disaster in more ways than just accuracy. For accuracy, if one is very close to the bottom of the pressure envelope, accuracy can also suffer greatly from a .1 grain decrease but other than from a "S.E.E." or "pressure excursion" no physical damage is likely to occur. | |||
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uuuuhhhh, considering that most (all) of the scales that reloaders commonly use, both electronic and balanced, are guarenteed to be accurate to (only) .2grs, how are we determining that .1 is causeing such dramatic changes of any sort? I have a Lyman 1200 and it's said to be accurate to .2grs; I have a Ohaus 10/10 and it's accuracy guarentee is .2grs. And I've proofed them, one against the other, and they agree. So, my question again is what sort of eq are we using to determine .1gr? Aim for the exit hole | |||
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new member |
Two items need my input. 1. Weighing cases. My hunting cases are weighed plus or minus 1 grain...that is from a bunch I will group 191.0 to 193.0 grains. For my long range shooting I tighten the parameters to plus or minus 1/2 grain. For those of you who are skeptical, go out to your car and, say its a 6 cylinder, change #1 to 6.8 compression, #2 to 7.9, #3 to 8.7, #4 to 8.1, #5 to 9.2 and #6 to 7.1 and see how it runs. 2. scales. My digital weighs to 0.1 grain, my beam scale weighs to 0.1 grain. I could certainly check a charge on both but I don't. As long as my digital says I have 72.0 I am happy and when I want 72.2, it will indicate that for me. Doesn't get any simpler than that. One needs to think clearly when reloading and having a mental f--- will not produce a good product. K.I.S.S. is an excellent rule to follow. | |||
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The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Guns, Politics, Gunsmithing & Reloading Reloading Have you ever had dramatic changes in accuracy with .2 of a grain upd info
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