Brass not fire forming

[Tommie]

It happens.
Starline is good serviceable brass but I doubt Starline would claim it’s a paragon of consistency. Even top-tier brass varies from batch to batch.
When I’ve gotten rounded shoulders the brass later got loaded with a full AI powder charge and all was well.

 

[nmkid]

I have always jammed about .015-.020 and usually load with 1.0-1.5 grains under the max for the parent case. There have been no problems.

 

[jwv2001]

My experience with Ackley Improved cases started when I bought a Cooper M21 MTV in 223AI. I read everything I could on a reliable way to form brass. Practically everything I read at the time proved to be bogus.
Never use any kind of lube on the case. Don't anneal the cases before hand. As a matter of fact, if anything, you want the cases as clean as possible. You need the case to adhere to the chamber in order to blow out the case walls first, then the shoulder. Understand that the key to the AI case is a 40* shoulder and a straight walled case.
Using lube or annealing will cause brass to flow into the neck.
I found that the best process for case forming was to just shoot a fairly good load of the parent case. The process that Ackman described is mostly the way I do it. I found that with the .223, the volume of the case increased 12%. At the time, there was not much data available, so I added 12% to the .223 data.

 

[Webster]

In the past, I've fire formed 500 .243 winchester cases in my Savage 12FV 243 AI with every one forming to satisfaction. Recently I purchased 100 pieces of new Srarline brass and had three or four rounds that after three firings had very rounded, unformed shoulders. (See case on right) Wondering if anyone has had this issue. Thanks.

??? 50,000 PSI should have done the job. Are you shooting light loads?

 

[Bill Norris]

Hey Bill, you're saying .020 into the lands?

Yes Sir. My builder recommends this for blowing out A I brass. So far I have had great results doing it this way.

 

[DLCrocket]

Compare the weight of the problem cases against the good ones. You might find the problem cases are heavier, maybe thicker. Thus not forming.

Thanks Bill. Did some weighing and didn't find any significant difference with the rounded shoulder cases. Some of the "good" cases were heavier and some lighter and some about the same.

 

[DLCrocket]

Thanks Bill. Did some weighing and didn't find any significant difference with the rounded shoulder cases. Some of the "good" cases were heavier and some lighter and some about the same.

Sorry, not Bill, 6.5

 

[NZ_Fclass]

I use Starline to form 6.5 SLR - It's not so easy as using Winchester or Remington brass, which forms better in the die ( neck lengthened, shoulder to 30deg) I need to neck turn, to reduce tension due to thicker brass and then fireform to get sharp edges etc. Which I do with a full load of H4350, during club matches. I have foreformed 243AI in the past using US "domestic: brass, mostly with 100% 243 Win loads of H4895 and 85g bullets in the lands. The rifle was fairly short chambered varminter/deer rifle, 10 twist.

 

[243winxb]

42 grains of H414 and 70 grain Sierra Blitz Kings

Looks like a standard 243 starting load @ Hodgdon.
If the rifle is a 243 AL Low Pressure problem. . Powder needs a magmum powder, also.

When i shoot 68 Berger or 70 Sierra with IMR 4350 in a standard 243 Win, the necks doesnt even expand, unless a maximum load.

modulus of elasticity- Cartridge Brass- Material is 70 copper/30 zinc with trace amounts of lead & iron , called C26000. Material starts to yield at 15,000 PSI when soft (annealed), and 63,000 PSI when hard. Material yields, but continues to get stronger up to 47,000 PSI when soft, and 76,000 PSI when work hardened. Modulus of Elasticity is 16,000,000 PSI. This means to pull a 1.000 inch long strip to 1.001 inch long induces a 16,000 PSI stress. So if you pull a 1.000 inch strip to 1.005 inch long, you get about 76,000 PSI, which is the max obtainable.

 

[Ackman]

You must be joking, or I'm misreading your post. Start at the max and go up? Maybe you mean the max for the unformed case size, but still . . . . If this is how you do it, I don't want to be next to you on the line.

Yes, I meant max load for the parent, standard cartridge. Yes, that's how I do it. Works just dandy......even a max book load for the standard cartridge is mild load in the AI case.

 

[SD guy]

Looks like a standard 243 starting load @ Hodgdon.
If the rifle is a 243 AL Low Pressure problem. . Powder needs a magmum powder, also.

When i shoot 68 Berger or 70 Sierra with IMR 4350 in a standard 243 Win, the necks doesnt even expand, unless a maximum load.

Good observation. & perhaps explains everything. Seems the op may have left room to work up more than 10%..

 

[Big Mc]

In the past, I've fire formed 500 .243 winchester cases in my Savage 12FV 243 AI with every one forming to satisfaction. Recently I purchased 100 pieces of new Srarline brass and had three or four rounds that after three firings had very rounded, unformed shoulders. (See case on right) Wondering if anyone has had this issue. Thanks.

More powder. and hard jam.

 

[DLCrocket]

After trying more powder and .020 into lands these few cases still had rounded shoulders so they are going to the scrap pile. Thanks for all the suggestions.

 

[Straightshooter1]

After trying more powder and .020 into lands these few cases still had rounded shoulders so they are going to the scrap pile. Thanks for all the suggestions.

Annealing is such an easy thing to do to take care of that kind of issue.

 

[Dfish1247]

How much more did you put in and was it still h414?

I used varget to make 243ai. I did use 90% load for regular 243, not ai with 87gr sierras jammed in the rifling .010”. What I understand is jamming is required to hold the case in line and up against the bolt face so it can’t wiggle while forming. Took two firings for the sharp shoulders, but the first ones were nowhere near as rounded as what you have. DO YOUR RESEARCH BEFORE TRYING WHAT I DONE. Might not be the most proper way, but it worked and continues to work for me.

Varget is a hair faster than h414, so there may be something to using a spicier powder. But, a couple pieces of brass in the garbage vs something broke, not the end of the world.

 

[DLCrocket]

How much more did you put in and was it still h414?

I used varget to make 243ai. I did use 90% load for regular 243, not ai with 87gr sierras jammed in the rifling .010”. What I understand is jamming is required to hold the case in line and up against the bolt face so it can’t wiggle while forming. Took two firings for the sharp shoulders, but the first ones were nowhere near as rounded as what you have. DO YOUR RESEARCH BEFORE TRYING WHAT I DONE. Might not be the most proper way, but it worked and continues to work for me.

Varget is a hair faster than h414, so there may be something to using a spicier powder. But, a couple pieces of brass in the garbage vs something broke, not the end of the world.

I used 45 gr of H414. Max for 243 win is 46. I agree on a couple pieces in the trash. I'll use them for practice when I start annealing.

 

[243winxb]

annealing

From Olin Brass
modulus of elasticity- Cartridge Brass-
Material is 70 copper/30 zinc with trace amounts of lead & iron , called C26000. Material starts to yield at 15,000 PSI when soft (annealed), and 63,000 PSI when hard.
Material yields, but continues to get stronger up to 47,000 PSI when soft, and 76,000 PSI
when work hardened. Modulus of Elasticity is 16,000,000 PSI. This means to pull a 1.000 inch long strip to 1.001 inch long induces a 16,000 PSI stress.
So if you pull a 1.000 inch strip to 1.005 inch long, you get about 76,000 PSI, which is the max obtainable.

 

[searcher]

For a case to round off at the shoulder like that, it is a clear sign that there is excessive headspace (as is expected when re-forming of an improved chambering) which is best dealt with by either using a false shoulder or jamming the bullet to hold the base of the case against the bolt. Just too much room in that forward chamber area.