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I have loaded a ton for bolt action rifles and generally have no problem finding an MOA load or near MOA load and I use the OCW method. I have a VC 9,3x74r and I have it was regulated with norma factory 286 grn ammo. Do I just the same basic approach...make a bunch of loads say .4 grains apart and see how well they shoot or is there some other process. 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 I do is prep and prime 50 cases and head down to the range with my press, powder measure, chronograph, loading manual or notes in the case of a vintage double. I usually have a few different powders and bullets I'm going to try depending on what I'm looking for. I then load up 4 rounds at a time shooting over the chronograph and making adjustments in 1 to 2 gr increments as I go. It has worked great every time. | |||
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I load mine at home in various weights and take them to a friend's property with chronograph. Not allowed to shoot above 8mm on a range here (well, there is one range, 4hrs or so away!). If it is a Norma factory load, you should be able to get that load. DRSS | |||
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Mike, first off do you have access to a chronograph? If so, then take six rounds of your factory ammo and set up two identical targets at the distance engraved on your back sight. Place these targets side by side and fire six shots very carefully right barrel on the right target and the left barrel on the left target with the same hold on the bull. Fire one shot right barrel on the right target, and the left barrel on the left target. Let the barrels cool to room temperature. Then fire the right barrel again on the right target and the left barrel on the left target again let the barrels cool, fire one more from each barrel on the target for 3 shots from each barrel. what you want is the average speed of that factory ammo, and find the center of each barrels individual three shot group in relation the other barrel and the aiming point on each target. Each barrels individual group center should be on it’s own side of the aiming point about the same distance on it’s own side of the aiming point. This will tell you how well the rifle is regulated with the factory ammo. This must be known before any hand loading is done. Now you need to load the experimental rounds to find a common speed with the factory ammo, and see if the individual groups open or close especially if you will be loading different bullets of the same weight. This will give you a starting point to move slightly up or down in your load to get a good regulation. What you are looking for is the centers of each barrel individual group. If the centers are crossing the speed is too high, if they are shooting wide they are too slow. A proper regulating load will be slightly wider that it is high for a composite group of both barrels. The double rifle is a law unto itself and the rules for a single barrel rifle will not work for a double rifle where all you need is a small group with the center near the aiming point on the target. The center of regulating composite group of both barrels will be perfect if the aiming point is half way between the centers of both individual barrel groups. Individual bullets will cross over into the other barrel group but the centers of each barrels individual group will never cross if the load is properly regulated. .....................................................................  ....Mac >>>===(x)===> MacD37, ...and DUGABOY1 DRSS Charter member "If I die today, I've had a life well spent, for I've been to see the Elephant, and smelled the smoke of Africa!"~ME 1982 Hands of Old Elmer Keith  | |||
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Mac, Thanks very helpful. It is an O/U rifle so I assume I just substitute the L/R concept with Upper & Lower? 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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Right! If your O/U is a single trigger that is not selective it will fire the bottom barrel first, then the top barrel, just so you can label the shots correctly on the targets. ................................................................Good luck  ....Mac >>>===(x)===> MacD37, ...and DUGABOY1 DRSS Charter member "If I die today, I've had a life well spent, for I've been to see the Elephant, and smelled the smoke of Africa!"~ME 1982 Hands of Old Elmer Keith | |||
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Mike, per your signature line: 1) You don't want to regulate a double rifle. 2) You don't want a double rifle at all. 3) What you really want is a Blaser thingofamajig component rifle system or some hooojaaa or other. 4) If you insist on a double rifle, you don't want a 9.3x74R, you want a 375FL. 5) You don't want a VC, you want a Sabatti. 6) To your credit, you did opt for the over / under instead of the proper SxS though!  | |||
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Mike, The most important lesson I learned after owning 7 doubles is to start with the lightest load recommended by the loading manuals. This will insure you can see the point of impact slowly converging onto the same general area. Hang up two targets. Shoot one barrel at one target then move onto the second target and barrel. Most likely the shots will be wide apart. Mark the target then shoot a load 1-2 grains higher, continue till both barrels shoot close without crossing. My biggest fear is when I die my wife will sell my guns for what I told her they cost. | |||
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Snowwolfe, Thanks very helpful. 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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Mike, Graeme Wright's "Shooting the British Double Rifle" is a great read. The posts above already talked about walking the barrels to convergence, so you've got the idea. What was a revelation to me was, with SxS, barrels were soldered with crossing bullet paths, and bullet impact point's height and Left Right location were changed as recoil drove the barrel up and away from center. The longer the bullet was in the rising, turning away from center barrel, the further off-center your shots. This was fascinating to me and a little counter-intuitive. Made me understand why faster loads in my handguns shot lower though, too. Verney Carron O/U double rifle in 9.3x74r. That sounds like almost perfect combo. Steve | |||
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There is enough information out there to get a starting point for your double. For me, I find a powder with an acceptable burn rate, use a charge on the light side of average, find the correct bullet type and weight, make a cast of the chamber and bore so I know the dimensions of the case and the diameter of the bullet to order a sizing die, get the correct dies and shell holder, and begin loading (again, on the light side). Four shots for each powder charge. I run the initial loads through a chronograph and keep track of where each bullet hits the target (25 yards to begin, then to 50) and note L1,R1, L2, R2. (I shoot the left barrel first and have done so for 20+ years). I will notice the bullet's 4-shot group coming closer and then cross when the velocity exceeds what it should be. Then I back off to the best group also noting if the velocity matches the published original ballistics, adjusting for my barrel length. Then, it is there. I just bought a .577 3" bpe a few weeks ago and when I get back from hunting in the Lower 48, this will be my project to start on along with a 12-bore double rifle that is also a new addition of the safe. Cheers, and good luck. Cal _______________________________ Cal Pappas, Willow, Alaska www.CalPappas.com www.CalPappas.blogspot.com 1994 Zimbabwe 1997 Zimbabwe 1998 Zimbabwe 1999 Zimbabwe 1999 Namibia, Botswana, Zambia--vacation 2000 Australia 2002 South Africa 2003 South Africa 2003 Zimbabwe 2005 South Africa 2005 Zimbabwe 2006 Tanzania 2006 Zimbabwe--vacation 2007 Zimbabwe--vacation 2008 Zimbabwe 2012 Australia 2013 South Africa 2013 Zimbabwe 2013 Australia 2016 Zimbabwe 2017 Zimbabwe 2018 South Africa 2018 Zimbabwe--vacation 2019 South Africa 2019 Botswana 2019 Zimbabwe vacation 2021 South Africa 2021 South Africa (2nd hunt a month later) ______________________________ | |||
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