Home Forums Hunting & Shooting AR and Tactical Rifles 556 + 62 grain M855

This is more of a reloading question but I'm putting it here for the larger AR audience. If anyone has quickload I could use a favor.

556 LC brass + 62 gr M855 bullets + H335 + CCI small rifle mag primers.

Can I get to 2900 fps with those components and what pressure would it be at?

I've looked at a couple "free" calculators online, and, yeah, I dunno if they're telling me the truth.

Thanks to anyone who can run those numbers for me, looking to see if powder on hand will work.

Hodgdon H335 this is 223 data.



2.260" 19.3 starting load 2,678 47,500 PSI 21.4 grains max and 2,887 from a 24 inch barrel at 53,600 PSI

If your getting 2900 from a 16 inch barrel thats pretty sporty.

Out of a 20" barrel with a 5.56 chamber, yes, you can get 2900, but you'll be a lot hotter than 54K PSI.

I didn't stutter in my OP.......

Already have the Hodgdon data, and I'm not asking about 223.

Factory M855 green tip runs 2940 average out of my 556 chambered 16" AR, clocked with a Garmin. I've sourced that exact bullet and wondering if I can safely duplicate that speed WITH H335, or not. I'm seeing indications yes, but want to know what quickload has to say.

Considering the factor powder is H335 (technically it's wc844 but the same difference) I'd see why you couldn't.

Mil-spec is 28.5gr behind the 55gr bullets. I don't recall the Mil-spec loading for the 62's off the top of my head.

If I remember right it's 26.1 grains of wc844 (NATO spec), generically, depending on the lot they're testing.

I just have a boatload of H335 and would like to use it instead of buying something else. About 3K of LC brass to load up.

Just go to max load and start increasing your load a couple grains at a time until you see pressure signs? How hard can this be?

Well, that's the plan, but it's nice to see some parameters to go by.

No??

I have a long time friend who uses 24.5 grains of H335 with a 62 grain FMJ out of his 16" Smith and Wesson AR. He claims it's accurate but does not know the velocity. If you aren't seeing signs of pressure at 24.5 that load sounds reasonable. Only a chrono will tell you the truth about velocity.

kwg

FA, how long is your barrel?

I tried to reload Quick Load tonight, but my old version won't work with my new operating system.

Sorry, can't help you there.

Yes you can. You'll be at 60k+psi. People do it.

But I hate to be a wet blanket - why? The M855 is a relatively [bleep] bullet and unless you have a need to penetrate a helmet at 400 meters, I wouldn't waste the powder and primer. But that's just me

Same issue here. Oh well.

Can you recrimp your primers?

Because I want to, but that's just me.....

Seriously though, 15 cents per bullet is pretty cheap shooting these days. Pre-price increase craziness powder and primer stock, no worries on my end.

Primers may back out at that level.

Duly noted.....

No. I don't see primers backing out until you are well over 60K. At least never did for us.

Last thing I would believe is quick load.

Load up in increments and see what happens. while the difference in 100 fps is really overall negligible unless you have to have the the least bit of wind drift possible... and since you are shooting ball 62 thats evidently not a factor, if you can get up to 2900 give or take its all good.

Couple things IF I had the desire... coated bullets. N500 series powders. Yup I know you have 335. And odd groove barrels.

Assuming you have the correct gas port size I stop pressure wise when I start getting ejector marks. Faint ones now and then are likely variable case volume issues but you are at the top end. But constant and heavy marks are more than I want. Verification of gas port issues comes to me somewhat by rim lifts. If the extractor is lifting the rim and you are getting ejector marks then you are ported to big likely. Get rid of the rim lifts or dont' have em but have heavy ejector marks then you would be on the top side of my comfort range and back off about half a grain IMHO.

For those that just have to.... you can make a primer crimping tool. They may even sell commercially these days. Loctite does not keep primers in. Long story of a guy that just had to have the last 50 FPS or so...

Thanks Rost.

I'm just looking to match up with the factory M855 already on hand. Can't see why I couldn't in the same brass with the same bullet.

Seeing how primer type isnt a factor in predictive software, 62 grain fmj, case capacity 31 grains, 26.5 grains 335 ~2890 from 16” barrel @ 59,000 psi.

Thank you Swifty

and if thats quickload I'd far from trust any of it. Seems on blind stuff we have to back up to known and adjust stuff by percentages... FYI.

You would think you could equal it. You may or may not. And just variations of where MV is read, chrono variances etc... I used to run federal match 22lr over mine before I shot for record so to speak to verify it was still correctly calibrated...

The man asked a question, I gave an answer, nothing more nothing less. Didnt ask anyone to trust it.
Fact is I have shot that load in LC brass without the mag primer and it was shall we say on the warm side.

Dont know if this helps you or not, but Hornady lists H335 with their 62gr fmj under their 556 nato data. Max is 25.4gr with a winchester small rifle primer good for over 3000fps thru a 20" barrel.

Fellers, come on.

I'm not looking to run a load generated by quickload. I wanted to know what pressure I'd be at, at that velocity, with that powder, to have SOME sort of idea what territory I'm venturing into on a workup. Rost doesn't trust QL...well I don't exactly trust "pressure signs" either. Mostly if they show up late to the party.

I have trouble running Hornady's site on this device. Do they give a pressure on that?

Never thought you were. I dont trust predictive software 1 iota, its fun to play with. When your pressure limit is 62K and it predicts 59K well folks thats a damn fine line.
I wouldnt trust Hornady data on anything.

no pressure listed but its listed under their 556 nato data in the 11th handbook. Intro to the nato data says loaded to 60,000psi, specifically for nato chamber only

Here is what I did
I found H335 on Hogden's web site. For a 62 grain bullet they have one load under .223. Their top load is 21.4 grains for 53600 PSI. I divided 53600 by 21.4 and came up with 2504.672897196262.
https://hodgdonreloading.com/rldc/


I multiplied the 2504.672897196262 times 24.5. The 24.5 is the load my friend uses. The end result is 61364.48598130841. In other words, just under 61370 PSI.

This is just one way I figure pressure. Other places may have it listed but this is the only one I can find and I did my own fuzzy math to determine pressure

Check Ramshot Xterminator and AA2230. Both are in the same burn rate and both are owned by Hogdens and are listed with Hogden's load data.

My friend claims he has seen no pressure signs so proceed with caution.

kwg

In case you didn't realize, I was simply adding to. Not at all doing whatever you think I was.

We have used it a lot. I don't have it but a friend does. Its pressures and speeds have been not even what I would call ballpark on non normal stuff.

I agree pressure signs can be tough sometimes. But you play with both and you get an idea. I suppose I was not clear on that. You can start with QL. We did with subsonic stuff. First round was 400 fps and stuck in the bore on a 300/221. It was calculated at 950 fps. But once you use both and trust neither totally you kinda get the idea.

Work it up. See what it says. I've shot 60,000 psi loads and burned out more than a few tubes doing it and never had a single issue.

ANd thankfully this conversation drug out the fact you shot it and verified it as WARM. Thats good info to go along with what QL predicted. I have seen QL pretty much spot on too. But like Sierra game kings its performance can be all over the place.

Well, with a side eye given to the QL stuff I started sneaking up on my target velocity of 2940 or so. 24.5 gr of H335 in my barrel gives 2910 fps, and 25.0 gr gives 2975 in this LC brass. So somewhere in the middle of that is my dupe load for NATO green tip and I'll be happily well under the NATO charge of 26.1 gr of wc844 . Primers are fine, and no signs of pressure. We'll get er dialed in shortly.

Oh, and absolutely LOVE that new Garmin chrono......