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prostreet
10-25-2015, 07:37 PM
I have been casting & shooting cast boolets for many years. I just started casting 55 grain .223 boolets with gas checks for my standard AR-15, rifle length. Using 25 grains of H335. Went our range to try them out. The boolets worked fine. Shot from 25 yards, to 200 yards. Grouped real descent. I didn't shoot too many rounds because the gun was "short stroking". That is when the rifle cycled, the empty cartridge was ejected great. The problem is the bolt didn't go back far enough to pick up the next round. Is the load too weak or do I need a lighter recoil spring? I had to pull the charging handle all the way back to chamber another round. Any and all help would be appreciated.
Thank You in advance.
Prostreet....:cry:

dot6
10-25-2015, 07:48 PM
There's a good chance that your gas tube may be getting plugged with lead, prohibiting sufficient gas flow to the bolt carrier. I learned this the hard way when I had a .22 L.R. conversion kit it one of mine. I had to take the gas tube off and hold it over a kitchen stove burner to melt the lead out, then scrub the residue out with a pipe cleaner.

anotherred
10-25-2015, 09:09 PM
Or do you have an adjustable gas block? Gas block not lined up over the barrel hole properly? Lead plugging (like mentioned above)? Which ever way, something is blocking the gas flow. 25gr of H335 is a fairly standard load (at least for jacketed, not sure about lead though) that should cycle the gun perfectly.

prostreet
10-25-2015, 09:28 PM
I only shot 8 cast boolits, I doubt it would clog with lead that quickly. I have allways shot jackets before with no cycling problems.
No adjustable gas block.
Thanks for the replies....

country gent
10-25-2015, 09:33 PM
Another issue is the bolt buffer there are several styles and or wieghts of them. Gas tube alighnment with hole in barrel, actual size of gas hole in barrel, mag spring tension, rough or dry bolt carrier, key out of alighnment and dragging. If alot of rounds aret thru this rifle then add in worn end on gas tube and gas rings on bolt. Another issue might be carbon build up.

prostreet
10-25-2015, 09:45 PM
I shot some jackets right after the cast without a hitch.

GabbyM
10-25-2015, 09:52 PM
No way 25 gr of 335 should not cycle a AR-15. 17.5 under a 55gr cast bullet should work or come real close to it. I'd say you need to check out the rifle real well. First thing that is common with home builds is the gas block or front sight not being lined up properly thus restricting part of the gas port. Then there is just a dirty rifle. AR's build up a lot of crud in the bolt lug area after a while. The AR chamber brush with the fat part that runs into the lugs along with a half pint of solvent may be called for. Then there are the gas rings on the bolt that need to be in good shape.

I used to get told by experts that IMR 4198 under 55gr jacketed at full power load was to light to cycle an AR-15. Hoey. My 223 cast load is a 60 grain bullet over 14.5 grains H-4198. It has cycled all three of my rifle length AR's. I keep them clean and use EP grease on bolts.

Smoke4320
10-25-2015, 10:12 PM
Possible bullets undersized . getting blowby
Need .002-003 over actual bore size

leftiye
10-26-2015, 05:51 AM
Try it with some more powder. Not enough chamber pressure when bolt opens to cycle the bolt far enough. Alternatively, late bolt opening due to insufficient gas - not likely as has been said.

1johnlb
10-26-2015, 07:04 AM
Possible bullets undersized . getting blowby
Need .002-003 over actual bore size

+1 either undersized or to soft of alloy. Allowing gas to go around the boolit. What is your alloy? Design? Gas check or not?

prostreet
10-26-2015, 09:15 AM
Sized to .224. Lee mold. Small flat point. Pure wheel weights, dropped in water while casting. Yes to the gas check.

aspangler
10-26-2015, 09:24 AM
I'll be watching thid thread closly. I am having the same trouble. Alloy is the same but boolit is lyman 224486 (?).
58 grain sized 225 with copper GC. 14.4 gr IMR 4198.

upnorthwis
10-26-2015, 09:50 AM
My opinion is that .224 is too small. That's the sizer die I got with a bunch of stuff in a package deal and I'm surprised you even got decent accuracy with it. I finally ground mine out to .227

prostreet
10-26-2015, 01:40 PM
Thank you for all replies. Will be watching for more.

1johnlb
10-26-2015, 02:51 PM
Hogden shows 25.3 grs 335 being max charge and 50k cup at 3200fps velocity. Is that your jacketed load or is that the load you worked up to trying to get the action to cycle with cast?

Tatume
10-26-2015, 02:56 PM
Cast bullets move more easily down the bore than jacketed bullets, and as a result similar loads do not develop as much pressure behind cast as jacketed. If you prepare otherwise identical cartridges, except one has cast and the other jacketed bullets of the same weight, will your gun cycle with the jacketed bullets but not the cast?

prostreet
10-26-2015, 03:58 PM
Yes the jacketed will cycle.

runfiverun
10-26-2015, 04:03 PM
sumthin is funny.
22.5 grs of 4895 will reliably cycle all of my AR's no matter what type of bullet I use.
I'm thinking your losing too much pressure in the throat area before the bullet plugs the barrel [or tries to at 224 diameter]


the 4198 load mentioned above is just not making enough gas volume to operate anything.

Motor
10-26-2015, 07:03 PM
Do some easy things first like giving the rifle a good cleaning. Then run that sucker wet with CLP. If that doesn't work move on to the other suggestions.

Motor

bnelson06
10-26-2015, 07:55 PM
Cast bullets move more easily down the bore than jacketed bullets, and as a result similar loads do not develop as much pressure behind cast as jacketed. If you prepare otherwise identical cartridges, except one has cast and the other jacketed bullets of the same weight, will your gun cycle with the jacketed bullets but not the cast?

This sounds about right to me. And sizing them that small will just make it worse. Did you slug the barrel to find the correct size for the boolit?

prostreet
10-27-2015, 10:48 AM
No on the slugging. I did measure my jacketed and cast boolets, they both came out to .224 consistently... Used a micrometer.....

prostreet
10-27-2015, 10:49 AM
Sounds like a plan.

bnelson06
10-28-2015, 06:23 PM
If you slug the barrel you will probably find that you need a .225 or .226 boolit

xringshutr
10-29-2015, 10:28 PM
I would definitely try more lube on the BCG first.......that load should cycle fine with any bullet/boolit. Then start looking at the gas system.

aspangler
12-29-2015, 03:08 PM
I'll be watching thid thread closly. I am having the same trouble. Alloy is the same but boolit is lyman 224486 (?).
58 grain sized 225 with copper GC. 14.4 gr IMR 4198.
Hey all. I have an update on this trouble in my AR. I bought a bunch of Alliant Varmint for my "J" words and thought I would try it with cast. Same boolit but I started with a 20 grain load of Varmint. 10 % below a starting load fro a 55 gr. "j" word. Acrruacy with this one load was about 2 inches at 50 yards. Not too good but it is a starting place. Full function in my carbine and no leading. Next trial will be with 20.5 and 21.0. May go a little higher if no signs of pressure or leading. Winter is a hard time to test loads because of the weather but I get back and let you know how this powder works.