How many reloadings from .300 BLK brass?

[LiveLife]

I have some questions about .300 BLK cases formed from .223/5.56 brass (I am shooting 16" AR with pistol length gas block):

1. Since .300 BLK cases formed from .223/5.56 once-fired brass has less of bottle neck, I am guessing they will experience less stretch that lengthens case. Is this true?

2. How many more reloadings are you averaging before you need to discard the .300 BLK cases formed from .223/5.56 cases compared to regular .223/5.56 loads?

3. Anyone experience longer case life from subsonic/lower pressure loads compared to supersonic/higher pressure loads?

Thanks!

 

[Walkalong]

I am only shooting supersonic, but am getting about the same brass life as I do in .223.

I had a batch I used for testing and finally had to scrap them. The first got tossed at about 7 or 8 firings, while some were over 10 firings. No split necks so far, even roll crimping most of them, and no internal signs of a rut, the primer pockets just get loose. This was a mix of RP 300 BLK brass and converted LC .223.

 

[Paddy]

Is roll crimp typical for those? I was under the impression roll crimps were only for wheel guns and lever rifles.

I was also wondering about case life and for subs I can't imagine that the lower pressures wouldn't extend case life considerably?

 

[LiveLife]

I have only used taper crimp for .223/5.56 loads and planned on doing the same for .300 BLK loads.

But many post using FCD improved accuracy so I plan to compare FCD vs taper crimp loads.

 

[Paddy]

Wait, is a fcd always a roll crimp?

 

[Walkalong]

I used no crimp on bullets like the 125 Gr TNT, but a modified roll crimp on the ones like the 125 Gr SST and 130 gr HC.

 

[Walkalong]

Wait, is a fcd always a roll crimp?

An FCD for rifles is a stab crimp.

Totally different from a pistol FCD which can be a taper or a roll crimp.

 

[LiveLife]

And I take it that since case life won't increase with .300 BLK over .223/5.56 loads, concern over using FCD is moot, right?

BTW, did you also observe an increase in accuracy with the FCD rounds?

 

[oldpapps]

I bought 100 300 AAC Head stamped cases and have converted many .223/5.56 cases to the blackout.

I don't remember a single case being culled because of head stretch roughness. Most from split necks (my fault I'm sure because I was lax in annealing) and the rest from lose primer pockets.

How many reloads.... one grouping of 30 went to 28 reloads before the lot was retired (if my sample group drops to 15, the lot is retired). Mind you, this was brass from my 'trash-brass' box that had been shot till it failed (usually me crunching the necks) some how. I have yet to re-form shoot-able .223/5.56 brass to .300 BlackOut. It just keeps on going. OK, I have 45 years worth of scrap brass to pick through.

I don't load hot (anymore now my loads are set) and primer pockets are lasting much longer. I don't think any will last as long as my old 45 casings do.

 

[LiveLife]

Good to hear. I am trying to reduce the .300 BLK reloading cost as much as I can as I have a feeling I may be tempted to plink .300 BLK rounds as fast as I do .223.

I am hoping to have some workable lower pressure loads with 150 gr X-Treme plated and 245 gr MBC lead bullets but still gathering powders to use. So far, I have W296/H110 and H4198 and looking for H4227/A1680.

 

[Walkalong]

BTW, did you also observe an increase in accuracy with the FCD rounds?

Sorry, that was a 7.62X39 round. It was just for the pic of an FCD crimp.

My most accurate load form my barrel is a crimped round. That does not mean crimped is better. I did not shoot that same bullet un-crimped. I am not going to either. I want crimped rounds for 300 BLK plinking. (It's a long story.)

 

[oldpapps]

"lower pressure loads with 150 gr X-Treme plated and 245 gr MBC lead bullets but still gathering powders"

I have (in my feeble little mind) had acceptable results using Lt'Gun with bullets in the range around 150 grains. I was getting started with 2400 and it was progressing until I got side tracked with 'Powder Coating'.

There are several usable powders, just about anything that works well in large/er Mag pistols.

I too am looking for multi-level loads. Cheap/fast/cheap/easy on the brass/cheap and hit close to the target The closer the better . I may have hit on me being cheap in that list.