I have been looking for a load i can just mass produce to go plinking around with my ar 15. so I started at the low end of things and have been working up i started at 23.5 gr of H335 and it was not even cycling so went up to 24 gr and it was cycling about 50% of the time so i went up to 24.5 and eventually at 25 gr i had a 100% cycling rate but at this point my bolt would still not lock to the rear after the last round was fired. i know its not my mags i have tested that theory. but i am at 25.5 gr. and still no lock out. i dont really want to burn up my barrel or over pressurize anything and i am all ready .2 gr above the recommended max load. i have been tracking my brass and so far there are no sign's of overpressure but i still would like a second opinion. any thought on way i am failing to lock out after last shot with this hot of a round would be appreciated.
- Thread starter frosty44
- Start date
Re: 55gr fmjbt with h335 ar.
Usually 25.3 of h335 with winchester 55gn fmj's works like a champ for me.
I take it your AR runs good with the normal .mil ammo xm193,m855..ect..?
Usually 25.3 of h335 with winchester 55gn fmj's works like a champ for me.
I take it your AR runs good with the normal .mil ammo xm193,m855..ect..?
Re: 55gr fmjbt with h335 ar.
I'm in the same boat as above. For all of my range/3-gun ammo I use 23.5 of H335 under a 55FMJBT with remington 7.5 small rifle primers, 2.260-ish COAL and have never had an issue with it in either of my ARs. One had a heavily overgassed 14.5" w/ pinned hider and standard gas block and the other is an 18" BCM with an adjustable. Very easy on the brass. Funniest thing is I had the best groupings with that as well when I first started reloading a while back. Never chrono'd it with thr 14.5" barrel but in my BCM 18" I get an avg of 2777fps although there's a fairly large spread and SD of 52.1fps - definitely a combo of the mixed/bulk prepped cases (wouldn't call it precision ammo by any means).
I don't know how your gun won't cycle reliably with 25.5g of H335 - are you running standard weight buffer, spring, etc.?
I'm in the same boat as above. For all of my range/3-gun ammo I use 23.5 of H335 under a 55FMJBT with remington 7.5 small rifle primers, 2.260-ish COAL and have never had an issue with it in either of my ARs. One had a heavily overgassed 14.5" w/ pinned hider and standard gas block and the other is an 18" BCM with an adjustable. Very easy on the brass. Funniest thing is I had the best groupings with that as well when I first started reloading a while back. Never chrono'd it with thr 14.5" barrel but in my BCM 18" I get an avg of 2777fps although there's a fairly large spread and SD of 52.1fps - definitely a combo of the mixed/bulk prepped cases (wouldn't call it precision ammo by any means).
I don't know how your gun won't cycle reliably with 25.5g of H335 - are you running standard weight buffer, spring, etc.?
Re: 55gr fmjbt with h335 ar.
I was going to ask the same question, but instead of h335, Im using varget. Are they similar in the amount of grains for the 55gr fmj?
I was going to ask the same question, but instead of h335, Im using varget. Are they similar in the amount of grains for the 55gr fmj?
Re: 55gr fmjbt with h335 ar.
Good point. Check the sealing rings on the bolt. Are they lined up, missing, or cracked?
Good point. Check the sealing rings on the bolt. Are they lined up, missing, or cracked?
Re: 55gr fmjbt with h335 ar.
I've run H335 loads from 23.0 to 26.5 through a couple of M-forgeries with no functional problems whatsoever, so I don't think it is an ammo problem.
I've run H335 loads from 23.0 to 26.5 through a couple of M-forgeries with no functional problems whatsoever, so I don't think it is an ammo problem.
Re: 55gr fmjbt with h335 ar.
Tear your upper down, clean it, reassemble it.
Tear your upper down, clean it, reassemble it.
Re: 55gr fmjbt with h335 ar.
223 55 gr H335 left to right Quickload pressure estimates and dial caliper measurements on extractor groove before and after:
unfired, extractor groove .329"
28 gr, extractor groove .329", 11% overload 69 kpsi
29 gr, extractor groove .329", 15% overload 80kpsi
30 gr, extractor groove .3295", 19% overload 92kpsi
31 gr, extractor groove .3320", 23% overload 106kpsi
Looks like the [real max load] is somewhere between 29 and 30 gr.
The [max practical load] would be ~ 4% less than [the real max load] = somewhere between 27 and 29 gr.
223 55 gr H335 left to right Quickload pressure estimates and dial caliper measurements on extractor groove before and after:
unfired, extractor groove .329"
28 gr, extractor groove .329", 11% overload 69 kpsi
29 gr, extractor groove .329", 15% overload 80kpsi
30 gr, extractor groove .3295", 19% overload 92kpsi
31 gr, extractor groove .3320", 23% overload 106kpsi
Looks like the [real max load] is somewhere between 29 and 30 gr.
The [max practical load] would be ~ 4% less than [the real max load] = somewhere between 27 and 29 gr.
