300 Fireball AR15 (Brass forming - post #150)

I'm getting closer to completion of my .300 Fireball :)


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Hey Doc, doesn't freebasing involve huddling over an open flame? You may just want to reconsider that when the cook spoon is full of smokeless powder. That might just be a wee bit painful. ;)

How to 'freebase' smokeless powder:

1 - Put a small amount in a spoon.

2 - Light it, at some safe distance from one's face.

3 - Inhale the vapors.

4 - Enjoy.

So you see, as setting it actually on fire IS a requirement for how I freebase my smokeless powder... I'm well prepared. :D

-M
 
Was at Wholesale Sports the other day and picked the last 1 pound can of W296. They still have it in the big jugs but I didn't think I'd need that much of it. They had Lil Gun as well but I already have loads of powder lying around so am trying to cut down on how many different kinds are on my loading bench.
 
Nice... 296 has been my favorite so far, followed by H110.

But - that's not the REAL reason I'm posting right now.

Yardie came over to my workshop the other day, and we had a look at his rig - trying to figure out what the heck was up with the feeding issues you and he have been having.

We made a few action-proving dummies (disassembled some of his loaded rounds so they were inert, then just re-seated the bullet, and used some of my once-fired brass to seat a different bullet).

Well, it was more than a little baffling. We were both scratching our heads about WTF was going on - sometimes the rounds would feed and then eject smoothly, and sometimes they wouldn't. Seating depth didn't really help, bullet type didn't really matter, etc.

So I had an epiphany today, thinking about it. My once-fired brass seemed to work better than his unfired/freshly necked-up brass.

In a nice, tight, match-cut chamber, the unfired brass (which has a good chance of being slightly off-center) swages into the chamber on the feedstroke and is a beeyotch to get out.

My once-fired stuff has been properly fireformed, and was WAY more reliable when doing the feed-eject test. Now, I never overtly noticed the feed-hand eject issue with MY rig, but here's the thing: I only hand-ejected maybe 3 rounds after feeding them, two of which were misfeeds due to a wimpy load anyway!

So... what I'm saying is that I'll bet good money that your rigs are misfeeding/jamming because the brass isn't fireformed - if you have some once-fired, make up some rounds (like I'm gonna do with yardie's rig this afternoon) and I'll bet you a beer that they'll work just fine.

Put plainly, the action-proving dummies I've made from 1xF brass have been smooth like a Hollywood lawyer, but the dummies from unfired brass are sticky like a whorehouse on cheap night. Both of them FEED, but as far as hand ejecting the 1xF wins any day of the week and twice if it's Sunday.

That's the view from here, gents!

-M
 
So we tested yardie's rig again today... using my once-fired as dummy rounds (sizing at the range, but we didn't have a hand primer... oops!) they fed and for the most part ejected alright.

His brass? Nope.

Very confusing. Especially since mine continues to function like a house on fire every time I play with it - so it's obviously not like the reamer is out of spec or anything. Very, very strange. I think we all need to have a three-way e-mail conference about this somehow, to bash our ideas and findings together.

-M
 
Definitely have to give the 1xF brass a go...hopefully that is the end of the issue.

Barring that...not sure what else to do? Doc and I, (mostly Doc) have trouble shot just about from every angle; this is the only action not tried (and appears to make the best sense) yet.

Of course, it'll have to wait for another 10 days...

@&#^$
 
Optimal barrel length

Now that you lads have had a while to play with the loadings is there any concensus as to what an optimal barrel length would be to allow for a complete burn in a sub-sonic load?

Or conversely, what barrel length would be minimum to allow for the maximum projectile speed given the restrictions of the casing volume?
 
We have been running barrel lengths from 9.5" to 10.5" which seem to be working well. The biggest thing was to make the things operate properly with the short barrel and pistol length gas system.

Any subsonic charge is gonna burn up completely in a fairly short length of barrel.

Agreed. Even with transonic and supersonic loads in my 10.5", there's no muzzle flash with the SPEX - indicating a pretty good burn. Although, the SPEX will suppress the flash on full-house .223 out of a 12" barrel too, so...

Regardless, it's all about getting a "shove" and then a short "glide" which certainly happens within 10-12".

I sure like mine - wicked fun to shoot.

-M
 
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