I recently acquired a 300 wby mag- mark v, and finally had a chance to sight in this weekend. I hit a big roadblock, and it is a problem I had not run into before. I loaded some rounds up with 200 gr. accubonds, 79 grains of 7828 ssc (it is the lowest load listed by nosler). I had no thoughts of this giving me any pressure problems, but it froze the bolt shut! I had to return home, and pound it open with a rubber mallet. The case filled the entire bolthead. Being a little shaken, I carefully loaded up 10 more rounds, thinking i had loaded a bad round. Round two at the range and another frozen bolt.
I never have, but should I back down from Nosler's lightest listed charge? It is a new rifle to me, is it possible it is a bad rifle? This has me stumped. It is 5% less than the listed max load, but it is way beyond a sticky extraction. So far beyond that I don't even want to try a different load/powder combo, or even factory loads.
I went to the imr website, and the load they list for a 200 grain bullet is much less than in the nosler load book- who's data should i trust? Any ideas on what could create this kind of pressure?
For the record, I have verified my scale is correct.

Len Hawkins

Check to make sure it has freebore???? I'm not sure what it should be though to tell you the truth. It should be almost impossible to seat on the rifling in a Weatherby with the correct chamber. Is this a new or used rifle.

Is your Nosler book listing 7828 or 7828 ssc? I know downloading a big case with slow powder can be as dangerous as overloading. I think I would be running to a gunsmith about now myself. Good luck.

It is used rifle. The freebore was a good thought, but the overall length is 3.60, a cartridge length of 3.69 contacts the lands, so there is plenty of room by normal/nosler standards.
Nosler list's it as regular 7828, but the label on the bottle say's "use 7828 data". I thought that may be it also, but the imr site say's they are the exact same burn rate, and the 7828 was designed to meter better- it does save approx 4% of case capacity, but these case aren't even close to full.

it's simply why we always start loew and work up.

I've found some serious hi pressured loads in the Nosler manual.

That is really odd that the max on the IMR website is only 78.3 and Nosler starts above that. What edition Nosler book do you have? I guess it must be new if it has the Accubond. I've always thought of Nosler data as kind of wimpy, maybe they changed their ways. Looking at the powders IMR does list for the AB they are all 1-2 grains less than the Swift. I guess I would interpret that to mean by IMR standards you are likely over by 2-3 grains. Does the rest of the data in the Nosler book make sense, I mean is it not an obvious misprint (the Max is less than the starting or it's identical to the RUM or something like that). Do they list any other IMR powders that track with the IMR website or any other powder website or is everything hot?

I'd still be spooked, but it sounds like you may have found an error. Maybe an email to Nosler would be in order.

I've loaded for quite a few weatherbies and can tell you if you are hitting the lands at 3.690" you DO NOT HAVE FREEBORE. All I can think of is someone might have shortened the barrel and re-worked the chamber. I set most my ammo at that exact same dimension 3.690" and still have a ton of freebore to go.
In one of my friends custom built rifles I blew primers when I started loads 1/2 between min and max with the 200 ab. His gun DIDN'T have freebore.

Using quickload as a model it thinks that 79 grains under a 200 ab would be making about 66k pressure.....certainly not enough to lock up a bolt. For some reason you are making even more than that. I would recomend dropping to at least 74.2 grains. QC thinks that would make 53,500 psi. I guess you could drop down to 73 and work up from there with a chrono. I'd be shocked if you couldn't work up to at least 3000 fps without pressure signs even without freebore but maybe you'll hit the wall at about 2950.
After I had this experience with my friends gun I made him buy a chrono as something he HAS TO USE when I load for him.

Also,,,,any brss besides wby or norma will usually have less case capacity making you load another 1-2 grains lighter. Just curious if you are using something else.

Take an empty case and just partially resize the neck so that it just barely holds a bullet lightly in place.

Put the base of the bullet barely into the neck and chamber the round. The lands should push the bullet back into the case.

This should get you a rough idea of how much freebore that you have in your rifle.

What is the typical freebore in a Weatherby? I seem to remember a formula like 1/2 caliber over COL or something like that at one time. I guess it would matter on the ogive of the bullet though...

That sounds about right....I know that a 180 ballistic tip is barely in the case on both my 300 wby's.
BELIEVE ME....that gun doesn't have any effective freebore and that makes a HUGE difference.
NOw for the good side.....you may have a more accurate gun that uses about 5-8% less gunpowder!!!

Kraky, some good info there. I re-read my original post. It should have read 3.96 to contact the lands. I had reversed the #'s in my post. I went back and averaged out 10 case/bullet combos for an average of 4.01 (ranging between 3.96 and 4.06). So it does have some throat.
What would you recommend as a seating debt/overall length as a starting point. I went strictly from the nosler pages as a starting point, and that seems as though it is not going to work for this rig.
The brass is factory weatherby. How well does your computer program work for you? I may try your min loads to get a start. Do you find that your data is more consistent than some of the bullet makers guidelines?
Thanks for the help.

WELL it appears you have freebore.

I thought we had it pegged but something is not right here.

I think we have one of two problems. There is something wrong with the gun or there is something wrong with the powder charge.

That load should not have locked up the bolt...that takes alot of pressure to do that.

Are you ABSOLUTELY SURE your scale was set properly? And it was reading proper? If yes then.....I think you should try another powder totally. If you have some 150 grain bullets around I would try them with some 4350 or something. Could you do that?

If we get problem velocity with another powder I thinnk it would be time to try and track down the former owner of the gun and find out his experience or take it to a gunsmith for a good look over and borescope check.

I'm suspecting bad powder....bad scale....what can you tell me??

For a scale check I keep my old manual scale around even though I use an electronic one. Another quick check is I like to weigh a bullet that is about the same as my charge. Got a 75 gr 25 cal or something laying around. They are not close enough to calibrate with but a pretty accurate check.

Got any pics of the fired brass and primer? I've never locked up a bolt, always looking for a chance to learn something.

I checked the scale before I loaded a new batch. 200 gr accubond-200.2 grains, 45 gr hornet- 45.0 and I tried a 110 grain accubond and it scaled 110.1. So I don't think its the scale.
I'm going to build a batch with some 4350 or 4831, minimum listed loads. I will probably use some 180 grain ballistic silvertips.
Kraky, the powder was a brand new bottle of 7828ssc- I bought it specifically to build loads with this rifle. These were the first loads that I had built for it.
I had completely cleaned the bore with hoppes #9 and hoppes benchrest copper solvent, so I don't think a dirty bore contributed.
I bought the rifle from a good gunsmith.They had test fired it and that was it. We have done a ton of business with them over the years, and they have always been square with me. If there is a problem with the rifle, I'm confident they will do the right thing.
Where are you in MI Stainless- I'm in Brooklyn.

I really have to wonder if the wrong powder is in that bottle of powder. I've used 7828ssc and it was a perfect match to my older 7828.
It wouldn't be the first time this has happened.
Let me know what velocity you get with the 4350 and 4831 and we'll run it past quick load and see if it seems right.
It sure sounds like you did EVERYTHING RIGHT to me.

For whatever reason there are huge differences in brass for the 300 wby. FWIW I took 3 FL sized, primed Wby cases and 3 Rem cases and filled them with IMR7828(not SSC). The Wby cases will hold 3.8-4.3 grs. more powder. If you use rem brass you should reduce your charge 3 grs.

I had my 300wmMkV loaded with 180bt/83gnIMR4831,pretty much on the limit of things,with rapidly expanding primer pockets, but still no stuck bolt.

Len, I've checked with Quickload 3.2; 79 gr. of IMR 7828 SSC behind a 200 gr. Accubond are supposed to give 4519 bar/65542 psi ! That's well beyond any safe limit! The real limit should be around 74.5 gr. Furthermore, I find it surprising that, after a frozen bolt, you loaded some other rounds with the very same load....to get another frozen bolt . The Lapua reloading manual states that, without a starting load, you should start 15% lower than the listed max load. Then, 83 gr. (incredible max load listed on #5 Nosler manual) - 15% = 70.5 gr. a good starting load. In the future, try to cross-check the listed loads on 2 or 3 different sources/manuals; none of them alone is the Bible.

Wildboar....you need to study the art of reloading more.......the wsm's are operating at 65K pressure......it is not "well beyond any safe limit". There are alot of cartridges that can be loaded in excess of 60K without any problem whatsoever.

My first suspicion would be the powder itself. I never trust ANY make of powder that is called "xxxxx Data Powder". What that really means in simple English is that it is NOT "xxxx" powder, but something that "should" be safe if you use the "xxxx" data.

One thing about cartridges of the Weatherby size and larger, they certainly DO have different reactions to the same large powder charges, from gun-to-gun.

I have a Model 70 that Roy Weatherby rechambered in the late 1940's to .300 Weatherby and it easily handles 83 grains of H-4831 and the Nosler 200 gr partitions. It also handles _95_ grains of TCI 5050 ball powder to give that same bullet 3,300 fps MV. BUT, my rifle has at least 3/8" (about 1 & 1/3 calibers) of freebore, and similar loads in any other .300 Weatherby would probably just be a long pipe bomb.

If I was you, I'd both drop my load to about 73-74 grains of powder, and I'd use REAL, CANNISTERED 7828.

Kraky, according to Quickload, the MAP (Max average pressure) of WSM cartridges, is 64542 psi/4450 bar, the Weath. cartridges MAP is 63817/4400 bar. At 64000/65000 psi anybody is well beyond any safe limit; Len tried twice and he got 2 stuck bolts.

Alberta Canuck.....7828ssc is not a wierd powder. It is the newest version of I7828. It's got the IMR label on it but techinically IMR doesn't even exist anymore. I don't know if Hodgdon will continue to offer the older I7828. There is nothing funky about 7828ssc....its just the new kid on the block and the can that I tried reacted exactly like my older long cut 7828.

Wildboar.....quickload has no way of factoring in freebore. Quite often it predicts too much pressure for a normal weatherby rifle. Len didn't get a frozen bolt because he "might" have hit 65,000 psi....that probably wouldn't have even left an extractor mark on his cases. He probably hit somewhere near 80,000 psi to get the reaction he got. All data including quick load predicts he shouldn't have had a problem.....but he had a HUGE problem and that's what we're trying to figure out.

quote:

Originally posted by makeminestainless:
Check to make sure it has freebore???? I'm not sure what it should be though to tell you the truth. It should be almost impossible to seat on the rifling in a Weatherby with the correct chamber. Is this a new or used rifle.
Good luck.

Freebore is critical. I have a 300 Wby reamer that is ground so tht it cuts a throat like a 30-06. With factory loads I sometimes get a sticky bolt, so handloads are required, but it really shoots great. If I were to sell it, I'd rethroat it to Wby specs, so the next guy did not have a problem.

quote:

Originally posted by kraky:
...All data including quick load predicts he shouldn't have had a problem.....

Not true, Quickload pointed out that 79 gr. of 7828 SSC, behind a 200 gr. Accubore is too much, and might have caused a 65.000 psi of pressure (or more). Furthermore, the IMR website, suggests, for the plain 7828 and a 200 gr bullet, a starting load at 73 gr. and a max at 78.3 with the mention: "NEVER exceed the load listed here". Anyway it's not my problem, and I don't want to start a flame; I suspect an excessive load, you suspect a freebore problem, that's all .

Wildboar....I don't want to keep this going either. But believe me 65k isn't causing the problem. And because we've determined that he does indeed have freebore.....I think there is something wrong with that lot of powder. But we'll know more once he tries some different powder. It would have been really great if he had a chrono going for those shot's that froze the bolt.

quote:

Originally posted by kraky:
Alberta Canuck.....7828ssc is not a wierd powder. It is the newest version of I7828. It's got the IMR label on it but techinically IMR doesn't even exist anymore. I don't know if Hodgdon will continue to offer the older I7828. There is nothing funky about 7828ssc....its just the new kid on the block and the can that I tried reacted exactly like my older long cut 7828.

Okay, I can understand that. I misunderstood the earlier posts for whatever reason, and thought he was using something called "7828 data powder". 7828 SSC certainly IS a cannistered IMR powder, regardless who makes it and who owns the company.

In every single "factory" 300 WBY rifle I ever worked on 82-83 gr 7828 was max for the 200 gr Accubonds at 3050 fps or so.

Again every single rifle was factory sako or WBY.

I guess another question (the answer may be above and I may not recall it) is how old and of what make is his brass?

Though newest brass, of the proper thickness and anneal intended for cartridges such as the .300 WSM, may be intended to run at 65,000 psi, is it possible his brass does not meet that description?

I know that in the "old days" (as recent as 15-20 years ago, even "high intensity brass" cases were said to flow severely at 70,000 p.s.i. Perhaps that is why some of his cases are locking the action and some are not...too much pressure for the design specs of his cases. And even though his average max pressure may be 65,000 p.s.i., that probably suggests at least some individual rounds up in the 70,000 p.s.i. area. (And, lets face it, no computer is a firearm. A computer is giving us estimates, not real, emperical, data.)

I know one thing for sure, whatever the problem is, he had better either have good insurance (and be clinically masochistic) or quit using those loads.

Well, I'm glad I've gotten such a response, even if it was due to a mistake I may/may not have made.
Wildboar, I reloaded fresh rounds to ensure that I hadn't created a mistake in my original set of loads. The first six that I loaded had 0 signs of pressure issues- no unusual primers or case issues. Since I can admit being human, my first inclination was to think I had misloaded the round. I had after all used a trusted source (Nosler) for the load. I used their lowest suggested load, as I always had. Maybe that is ultimately the mistake, trusting one source for load info. That will not occur again.
I guess when it comes down to it, who do you trust for data? Do you follow the bullet makers, the powder makers, a computer program- who's to say what is right and what is wrong. Who's to say what is safe pressure and what isn't. We have some guys who responded whose rifles would eat up 79 grains, others who think that would be grossly overpowered. I guess I'll back them up a minimum of 10%, but if you pick the wrong source to start a load from, it still may be hot. I guess that I can thank god that my rifle and myself are in one piece, and keep this locked away to never trust a load regardless of the source.
For the record, my next attempt will be with 68 grains of 4350, pushing a CT 180 gr. ballistic silvertip. What do your load programs have to say for that one?

Thanks,

Len Hawkins

QC guesses 51k pressure at 2924 fps.

Do you have access to a chronograph?

Your last post has me confused.....you ran a number of the 200 grainers without a problem but all of a sudden you had one that froze the bolt??

Len (and other members too), please understand that, since I'm not anglophone, I sometimes have trouble to exactly express my thought and I'm not a smartie. I've possibly misunderstood something, I thought that you shot only 2 rounds, getting 2 stuck bolts. As for the Nosler manual, since it doesn't suggest starting loads, I would refer to the Vithavuori manual "...if there is no indication of the starting load, use 15% lower charge than the listed maximum". Quickload indicates that 68 gr. of 4350 behind a CT 180 gr. Ballistic ST should be a safe load; you could start at 65 gr. and working up; 71 gr. should be max. Anyway let me suggest you another (probably better) load: from 74 gr. to 79.5 gr.(max) of 7828 SSC.

Kraky- the bolt did not freeze until the 6th round- the first 6 had zero pressure signs. If I was a little more skillfull I could post photos of one of the first 6, then the hotties. It is intimidating.
Wildboar, the suggested load with 7828ssc max is more than i had tried the first go around. I really wish i could post the photo's of the brass that froze the bolt. It is way beyond anything i have run into before. And I never did answer your question on the brass.It is all relatively recent weatherby factory brass (not the older tiger boxes), once fired, polished, full length resized, trimmed, well prepped brass. I'm just going to back the loads down, with 4350 from a can that has given me consistent results in my 300 win mag. For the record, the max load w/ a 180 grainer and 4350 is 76 grains (according to nosler). IMR has it for a 180 grain bullet w/4350 as 68. 0 starting and 72.6 max. Another thing I noticed when comparing the loads for a 300 win mag vs a weatherby mag- the win mag had reported presures for max loads at about 62-63k. the weatherby loads were maxed between 53-54k. Any thoughts on why the big difference?

quote:

Originally posted by Len Hawkins:
..Any thoughts on why the big difference?

No idea...

Len....I'm beginning to wonder if your scale hung up on the two rounds that went ballistic.
The fact that you had 6 that were just fine before the bad one starts ruling out the consistant things.
You really need to get a chrono going for your load testing. No reloader should be without one in my book.
In the meantime I would recomend that you double weigh your charges by topping off your charge to the weight desired.....pull the pan off the scale....then put it back on for a 2nd weighing before dumping into the case.
If you scale is occasionally sticking it will tell you it has a problem by not coming up with the exact same weight both times.
By the way, I found an older printing of IMR data and in the good old days when they really printed max loads it said that 83 grains of 7828 was the MAX load for a 200 grainer. Now the accubond makes just a tad more pressure than some other 200 grainers because it is so long. IN those days when they printed max load it meant MAX load and you might not make it there without some pressure. Still if that lot of 7828ssc is a good lot you should have not had a problem at all and possibly could have even worked up a tad more. You should be able to make it to 3000 fps easily with 7828 and a 26" 300 wby rifle.

I really am starting to think it is bad powder- I have double checked everything. I try to be extremely thorough and consistent, and that is why I weigh evry charge. My powder drop is adjusted to within 1/2 grain, and trickled to balance. Every time. I am half convinced to peddle the rifle and start with another, but the other half say's there is no way in hell I can't make this thing drive tacks! I have some other loads built, so I will sneak up on it over the next few weeks.
It is relatively comforting to know that IMR had the same loads that you find in Nosler, and in some other resources.
And, a chrony is on the list. That and as digital scale/powder master type combo.

Len...I'm really thinking your scale isn't working right. If you had a bad lot of powder it would be bad for ALL your shots. Anyone who's loaded for years and years and never had a scale that "hangs up" is either a "fibber" or darn lucky.
Think about it...if the rifle had a problem it should have happened every shot......if the powder was bad it should have happened every shot. The only other thing I can think of is a pinched bullet by missing trimming but I still would lean towards the scale "hanging" up on you. Be sure to double weigh everything and see if you get a inconsistant reading once in a while.
ITS HAPPENED TO ME .....if you reload long enough it will happen.

If 6 were fine then it is not the powder and a chrony will not really help you yet, although they are great to have for reloading in general. I guess you had to have the scale "hang up" on those or something. I assume you are using a manual scale. Slow powders in that big of a case should not change that much from a small drift in weight, it's impossible to double charge and a small difference in COL with freebore won't cause it, neither would a different primer IMHO. I have seen pressure (and velocity) rise pretty dramatically when rapid firing a high intensity round due to heat, but I've never seen pressure signs like that.

If you can't figure out how the last 2 could have had significantly more or different powder (or a different bullet) I'm stumped. I'm not saying you made a mistake, just that I can't think of anything else that could cause that much of a difference. I can't imagine that much variation within the same can of powder.

Good luck no matter what you do with it. BTW I have a 300 Weatherby in the Vangard. I really like it but would discribe it as "finicky" to find good loads for. I think the freebore makes it a little more challenging. I have found a combination that puts full power 200gr A frames 1MOA, but it took a while. I'm up by Jackson - Marshall area.

Thanks to all that responded. After building some loads with IMR 4831 (67 grains) and still getting sticky extraction, the rifle went back to the shop where I got it. As a test, we fired a round of factory ammo, and guess what, another sticky extraction. We had to tap that one out with a rod. Bottom line, it was a bad chamber in a factory barrel.
As suspected, they were willing to make it right, and either set the barrel back and rechamber, or refund me completely. Since there was nothing but bad mojo, I went the refund/exchange route, and now have a ruger 375 hawkeye to tinker with.

Wow--never heard of such a thing. I wonder why the first owner didn't deal with the problem instead of pawning off an unsafe gun onto unsuspecting people. Sounds like someone could have been hurt. But it still seems strange that there were rounds that weren't a problem and then some that were. Not sure I understand how the problem could come and go.
Good luck with the new gun!!

Now did you weigh every charge? or calibrate a powder measure with the scale and dump the loads from the measure? I've had powder bridge in a measure's spout, giving a light charge followed by an extra heavy one.