Pressure signs, lost three primers today

[Rick Richard]

Question for the group as another first year reloader.

In this scenario, if a guy has shot a half dozen over-pressured loads but there's no catastrophic failure, should there be any lingering concerns about the action? Anything you'd look over before starting another round of load development or keep an eye on moving forward?

If you get some issues where the rounds won't fire, then you will have to replace the firing pin spring.

 

[knapper]

I am shooting a custom 7mm-300 win mag. The rifle is a PTG blueprinted action with a br firing pin. Connected to a 26" broughton 1:9 twist barrel. Assembled by mirage ULR in Dallas. I am shooting Berger 195's twenty thousands off of the lands. Using H1000 powder, with a federal match magnum primer. Two thousands neck tension. I have almost 300 rounds down the barrel. My first 100 pieces of nosler brass gave out due to primer pockets being too loose. I shot almost all of them three times. So I bought some Norma brass, I also bought some win brass to test out. My max load is 72.0 grains of H1000. I sized the brass and loaded a ladder test in each type of brass. From 68.0gn up to 72.1gn in .3gn steps so I can find the pressure in each type of brass. The Norma kicked two primers in the mid range of my test. The win kicked one out about the middle of my test also. I never had a sticky bolt, I had ejector smudges toward the top of both of my ladders. My FPS was in the 3050fps range at the higher end of the ladder. I need some advice from you all, as I have only been reloading for one year. It shot some pretty nice groups, despite the three primers in the mag well. Thank you for your advice.

Member 103063.. Your post caught my eye for two reasons.. Your mention of Dallas and my first name is Dallas.. #2 is your rifle is almost exactly like mine.. Only mine is a Savage , Model 110, 29 inch seterian barrel, and I ran a ladder test but I have ran nothing but Hornady Brass and Winchester primers... The powder that I found to be the best working was the H 4350 and I have tried almost all that is on the market.
My speed is holding around 3050 and I get a .5 MOA consitantly, at 100 yards

Dallas Richardson

 

[keithcandler]

Knapper, which bullet are you using?

I would suspect that R#26 would be supurb!

 

[Toddxusmc]

ColoGuy970, as others have stated your pressure is way too high. The only way to achieve or keep the velocity you are looking for is to go to a slower powder. I have had great luck in my magnums(although not your specific caliber) with RETUMBO. The problem you might run into is case capacity, RETUMBO and other like powders require alot. The fact you are having issues with a powder like H1000 would dictate a slower powder US869, RE33 (maybe RE26), RETUMBO etc.
Please DO NOT take the advice posted by another advocating H4350 for your load. If you're getting blown primers w H1000, H4350 will be absolutely catastrophic(doubting the authenticity of that post). Im sure everyone with any experience will agree with me on that; going to a faster powder is not going in the right direction.

 

[Rick Richard]

ColoGuy970, as others have stated your pressure is way too high. The only way to achieve or keep the velocity you are looking for is to go to a slower powder. I have had great luck in my magnums(although not your specific caliber) with RETUMBO. The problem you might run into is case capacity, RETUMBO and other like powders require alot. The fact you are having issues with a powder like H1000 would dictate a slower powder US869, RE33 (maybe RE26), RETUMBO etc.
Please DO NOT take the advice posted by another advocating H4350 for your load. If you're getting blown primers w H1000, H4350 will be absolutely catastrophic(doubting the authenticity of that post). Im sure everyone with any experience will agree with me on that; going to a faster powder is not going in the right direction.

Agree too!

 

[wonderman4]

I would estimate your pressure levels at approx. 80,000psi.
Here is a decent article on reading pressure signs. Read it twice and pay attention both times.

FWIW, I do not believe in the mythical pressure ring as it is not an official part of a cartridge case and you won't find it on any SAAMI drawings.

The link to the article:

http://bulletin.accurateshooter.com/2011/04/evaluating-pressure-signs-in-reloaded-cartridge-brass/

 

[bigngreen]

I've found R26 to be the powder other than H1000 for the 7-300 Wins I've build, that said your running hot with a 195 and H1000. Also using ADG 300 Win brass is an upgrade all round! I would back of and find a lower node that gives you brass life and let the BC of the 195 do the work, if you gotta run over 3000 fps the a 28 Nosler is next up!

 

[tbrice23]

FWIW, I don't have a 7-300wm but do have a 28 nosler and I'm shooting 175gr bullets. Retumbo was pressuring too fast so I tried RL33 and found happiness there.

I'd say Retumbo or Reloder 33 in a 7-300wm with 195gr bullets would be the fastest burning powder I'd trust.

 

[keithcandler]

ColoGuy970, as others have stated your pressure is way too high. The only way to achieve or keep the velocity you are looking for is to go to a slower powder. I have had great luck in my magnums(although not your specific caliber) with RETUMBO. The problem you might run into is case capacity, RETUMBO and other like powders require alot. The fact you are having issues with a powder like H1000 would dictate a slower powder US869, RE33 (maybe RE26), RETUMBO etc.
Please DO NOT take the advice posted by another advocating H4350 for your load. If you're getting blown primers w H1000, H4350 will be absolutely catastrophic(doubting the authenticity of that post). Im sure everyone with any experience will agree with me on that; going to a faster powder is not going in the right direction.

Darn good advise!

R#26 has a very steady pressure curve, not like H1000. I would give it a try, also with Retumbo and #33.

When working in unknown areas, I shoot one shot and one shot only, increasing the powder charge 1.0g at a time, watching case head for pressure signs, chrono graphing the loads. Then start fine tuning. Most accurate charges are usually within 2.0g of first signs of pressure.

 

[SidecarFlip]

Too fast and too hot. I never load past 3000fps. Over 3000 fps eats lands.

 

[ColoGuy970]

I would estimate your pressure levels at approx. 80,000psi.
Here is a decent article on reading pressure signs. Read it twice and pay attention both times.

FWIW, I do not believe in the mythical pressure ring as it is not an official part of a cartridge case and you won't find it on any SAAMI drawings.

The link to the article:

http://bulletin.accurateshooter.com/2011/04/evaluating-pressure-signs-in-reloaded-cartridge-brass/

Thank you, I will read it twice

 

[nmbarta]

As mentioned Retumbo is a good stable powder that's just about right for this.
Do not even attempt to use 4350, that's good powder for a .260 or 308, not a 7-300.
I run retumbo in mine, you can pm me if your interested in load data.

 

[Shane Lindsey]

I found this one to be helpful...pictures helped.

https://www.primalrights.com/library/articles/understanding-pressure

 

[ColoGuy970]

As mentioned Retumbo is a good stable powder that's just about right for this.
Do not even attempt to use 4350, that's good powder for a .260 or 308, not a 7-300.
I run retumbo in mine, you can pm me if your interested in load data.

Hey nm, I do not know how to pm you or I would. I started loading for this rifle with retumbo. I loaded up to 73gn, and hit pressure issues. I never had any issues with case capacity. I was reading about how it wasn't as temp stable as H1000. That is why I switched to the H. I would like to hear more about what you are doing with it. Thanks again, you guys are a very valuable resource. Except that one h4350 suggestion.