I just wanted to write down some thoughts on this. It seems the 14.5 AR is very popular since everybody wants a short carbine. I also want a place to post my data where I can get to it from the range on my Iphone and hopefully help others duplicate military pressures. I also have zero doubt that this will start a decent discussion and bring in more expertise and opinions that I'm really wanting to read.

All three rifles I used had Full Auto Carriers made with Carpenter 158 steel, 5.56 Chambers, 1/7 twist barrels, M4 feed ramps, 4150 CMV barrels made by FN, HP/MP tested Bolts, Heavy Buffers, and were as Milspec as they come for AR-15's

Do NOT attempt these loads or data in a non milspec AR and certainly not in a .223 chamber.

So people love the 14.5 inch carbine rifles... you have to pin/weld a permanent flash hider onto it to make it 16 inches so why not just get a 16" barrel?

The loss in velocity is not worth it in my book.

I took my shooting chrony out today and used a 20" barreled AR and 16" barreled AR to test these 4 rounds

MK318 SOST 62 grn MOD 0 Factory round.
XM193 55 grn FMJBT Factory and Mine
M885 62 grn Green Tip Penetrator factory round (SS109)and mine

And finally My homemade MK262 Sierra BTHP SMK 77grn MOD 0 (Mod 1 would have the cannelure)

Black Hills will sell those loaded rounds but they are damaged/not fit for issue.... but Sierra does sell the bullet...so get that and ... Ramshot lists a load of 24.8 grns of TAC for 2,902fps, 61,500 2.260 length.

I loaded mine at 2.255 because the tips are not very uniform in length and I don't want them scraping the mags. I also reduced the load to 24.4 grns of powder since it was 103 degrees out today and I was seating the bullets further and you are dealing with super high pressures. I was in the shade today but it was hot none the less.

So onto the data....I took the average of 10 shot strings.

First was the SOST round. I have not duplicated it because I don't think Federal has the bullet for it available for sale. I've read it's close to a Trophy Bonded Bear Claw. It is an Open Tip not a Hollow Point.

So first string of USMC issued bullets....62 grn SOST OTM

20" AR -- 3150 FPS
16" AR -- 2950 FPS

Second M885 62 grn Green Tip Penetrator SS109

I tried to duplicate this load with 25.5 grns of H335. Next time I'm going to try the Ramshot TAC as their load shows 26.2 grns for 3219 fps. I didn't know an M885 could move that fast.

I first fired Factory loads, Federal Eagle, M885
(supposedly )the stuff issued to the troops...I didn't see an NSN number on the box like there was on the SOST's....I think these were maxed out SAAMI pressure rounds because the FPS...

http://www.kmike.com/Ammo/tm%2043-0001-27.pdf shows on page 10-18 3025 at 78ft from the barrel...

These were

20" AR 3080fps
16" AR 2970fps

My loads of 25.5grn of H335 for the 62grn M885 pulls

20" AR 3040fps
16" AR 2939fps

I will have to bump this up to 25.8 of H335 but I think TAC will be a better load for this as they have established data on it. I would love to see 3200fps .....I question that but I'm gonna try it.

http://www.ramshot.com/wp-content/uploads/2010/09/ramshot_handgun_rifle.pdf

Next was the homemade MK262 Sierra HPBT 77grn SMK using 24.4 grns of TAC.

20" AR -- 2750
16" AR -- 2600

I may go the full load of 24.8 grns to get the 16" AR more effective. I believe the factory loads for the MK262 call for 2750 FPS and I did achieve that goal with the 20" AR..but again it was hotter than u know what so my pressures were up plus I seated deeper to 2.255. These were accurate as ...you know what. Nice tight groups.

Last but not least is the XM193.

Factory Federal XM193 with the NSN Number

20" AR -- 3280 FPS
16" AR -- 3100 FPS

I have not duplicated this yet as I was Loading SAAMI pressures around 51000 not Milspec 61000 cups

My loads sucked with 24.8 grns of H335. That isn't even close.

According to this...

http://www.kmike.com/Ammo/tm%2043-0001-27.pdf

WC844 is close to H335. On page 10-3 it calls for 28.5 grns if I'm reading that correctly. That seems excessive for a 55 grn bullet to get it going 3250 FPS so my goal will be to use 26.1 of H335 and work my way up .1 grain at a time until I reach 3250 fps 15 ft from the muzzle with a 20" AR or 3100 fps with a 16" AR

http://www.frfrogspad.com/miscellq.htm#duplicate

So lets talk bullets for a second.....the Military says the XM193 FMJBT and the M885 62grn Green Tips must hit flesh traveling at 2700 fps to yaw and fragment.

So now....if we were to use a 14.5 inch AR, XM193 bullets would be about useless after around 150 yards and the M885 around 100 yards. No wonder Soldiers were complaining about performance of those two rounds. The M16 Stoner rifle has been basterdized to the point where it's ineffective by chopping off 5.5 inches of barrel and putting on a gas system that gives it a higher cycle rate.

So to fix the problem the Marines went to the SOST OTM MK318 round and the Army has switched to a new M885A1 round although the M885 is still used effectively on the M249 SAW ..but it has a 18.3 inch barrel and nobody is complaining about performance.

The SOST MK318 round was optimized for the 14 inch barrel.

The MK262 77grn round is doing well in all barrel lengths and all ranges and has a confirmed kill at 700 yards.

Those of you that want to stock pile Zombie Ammo and SHTF ammo need to consider the options when you made your decision on barrel length for your AR.

I got into an argument with an ex soldier at Cheaper than Dirt today behind the counter trying to sell me crap, that was in country last year, and said nobody uses Hollow points. I then proceeded to tell him about the MK262 and MK318 and how they are not HP's. He was pretty surprised and a little confused on the MK318 as well being an OTM (open tip Match).....talking about Geneva conventions....blah blah....

It is the Hague Convention that bans exploding rounds or those that open up and have controlled expansion. By calling the MK318 and MK262 rounds OTM (open tip match) they are not hollow points. They don't act like them either. When they strike flesh, they tumble, tips break off and they fragment at the cannelure...

All military rounds have the cannelure for two reasons....to crimp to avoid bullet setback and to provide a weak point for the bullet to break and fragment.


Here is a really good article about bullets that are far better in SBR's than the standard bullets everybody buys.

http://www.shootingtimes.com/2012/03/21/special-forces-to-civilians-black-hills-mk-262-mod-1-review/

I'm going to be to dupe the Hornady 75grn TAP next....Should be getting 2713fps out of a 16" barrel and 2820 out of a 20".

I hope this helps people better understand the confusion out there many people have with ammo.

The rifle is just one part of the equation. If you don't have effective, accurate, ammunition you are just shooting pencil holes in things with no effect.

Here is a really cool Ammo cross section.....just about every military round in existence.

The M885A1 I think is different now as it features a copper plug at the bottom now.

Ammo Cross Sections.

I forgot Primers....

At these pressures...60-61k you will start piercing primers if you do not use a primer with a thick enough cup.

Primers recommended for use in .223 Rem/5.56 semiautomatic rifle loads:

CCI #41, 450, BR4
Federal 205, 205M
Remington 7 1/2 BR

These are the ones you can readily get.....

I talked to a shooter today with the Texas State Rifle Association that is going to Camp Perry tomorrow, and probed his brain....

They(the team) load to milspec pressures every time. He uses Remington 7 1/2 primers. He cautioned against other small rifle primers that were standard like Remington 6 1/2 and CCI 400.

At those pressures you can/will start piercing the primers. The Federal 205/205M is the minimum in cup thickness of .022

Rem 6 1/2 - .020"

Rem 7 1/2 - .025"

CCI 400 - .020"

CCI 450 - .025"

CCI BR4 - .025"

CCI #41 - .025

Fed 200 - .019"

Fed 205M -.0225"


Jeff Lee was the guys name and really spoke highly of the Remington 7 1/2 for high pressure rounds. Said they were perfect for his matches and I guess all those precision shooters are using either that or one of the CCI .025 primers.

Ok, 25.9 grns of H335 Nets 3045 fps out of a 16" AR with a 55grn FMJBT.


I'd like another 60-75fps more so I'll move up to 26.2 and see if that is where I need to be.

Lots of work, Nice results and thanks for the post.

Goodness, Jeff! That's a lot of info there! Nice work! Is the H335 the stuff I sold you?

You're welcome. Most people I talk to stick with SAAMI pressure and do not use the their 5.56 chambers to their full potential when reloading.

They'll shoot factory high pressure rounds then load SAAMI for whatever reason. I have a new Chrony to play with and I had the week off and wanted to get my load data set for loading 5.56 rounds while I had the chance, and thought I would share my findings for those that did want to load to Milspec.

I'll be doing 9mm rounds(M882)for the M9 as well...115grn 1263fps +- 5 15ft from the muzzle.



yes sir it is!!

Great powder and great price.

Everybody that bought the H335 from you can safely duplicate these loads if they have a 5.56 chamber.

I'm going back to the range tomorrow with my XM193 loads with 26.2 grns of H335 and hopefully I'll have duplicated them precisely for everybody that wants to load 5.56 instead of .223.

I'll Also be taking some rounds between 25.5 and 25.8 grns of H335 for the 62grn M885 pulls to duplicate the factory US Issued SAW M249 rounds. I'm really close with those.

I'm going to try a few with the high pressure TAC as well. I may not get to those until late and I'm a little hesitant to try those in Remington cases.....3200 fps for a M885....

TAC 62 MIL M855 23.6 2,940 26.2grns 3,219 62,350 2.260

http://www.ramshot.com/wp-content/uploads/2010/09/ramshot_handgun_rifle.pdf

I think I'll call them and see if they used a 24" barrel or something for those velocities.

Another few notes....all rounds factory and mine have all had flattened primers.

That is a big pressure sign and most people back off from that.

Your rifle can take it if you have the proper setup. These rounds are around 60-61,000 psi milspec pressures. I'd be shocked if the primers were not flattened.

Make sure you double check your brass for cracks. You do not want any leaks. Make sure you primer flash holes are clear and uniform, and your primer pockets are uniform as well since you can't crimp the primers or at least not that I know of.

If you have a primer that does not set stiffly, do not use that case for a milspec load. Use it as a .223 unless it's really loose then just toss it. You do not want any gas leaks at these pressures through the primer into your bolt.

I am also crimping my rounds except for the 77 grn Sierras. Next lot of Sierra SMK's I get of those they will have the cannelure....although it doesn't look like it barely scratches the surface in pics I've seen. Hardly worthy of the word cannelure.

Anyhow, A bullet setback at these pressures would be devastating. The military contracts say crimp the ammo, I use a Lee factory crimp die and I crimp the ammo.

Lots of good info here.
Thanks for taking the time to document it.

Thank you for sharing.
That cleared up a lot of the "smoke and mirrors" I see concerning 223 vs 556.

Welcome, stay tuned for more, I'm not done by a long shot.



You are welcome as well. There will be more myths to dispell.

Ok, I called Western Powders, (Ramshot Tac) (406)234-0422 and left a message.

I already forgot the guys name but I got a call back...

My question was what barrel and chamber did they use for that 62grn M885 5.56 load going 3200 FPS. My confusion was the top of the page said "heavy/long bullets 24 inch 1/7 - 1/9" I didn't consider the 55 grn and 62grn "heavy/long" unlike the 75,77,80, and 90 grn bullets. So I wanted to make sure what barrel was used for the light bullets.

His answer...

24" stainless steel, with a .223 chamber..forgot to ask the twist. They test all the 5.56 loads in a .223 chamber because it creates high pressures and if it is safe in that...well then it is more safe for us with 5.56 chambers. And that extra 4" of barrel sure helps that bullet scoot past 3200fps.

Since the Factory M885 load is 3080 fps out of a 20" and 2970 out of a 16" I'm just going to start at 25 grains of TAC and work my way up until I can find a magic number that is around or above factory without going past 26.2 and shoot for accuracy.

See if I can get a decent group around 3000 fps out of a 16 inch AR. That will make it just beyond a 100 yard gun with the M885 round keeping above that critical 2700 fps.


For H335 I'll start at my 25.5 and work my way up to 25.8 or 25.9 since I'm so close to factory and see what is the most accurate load in the 16" AR.

And it gets more interesting....

I just happen to have a stainless 24" Wylde chambered varmint profile 1/8 5R barrel sitting on a Palmetto lower with ACE A2 skeleton stock.
With 75 grain A-Max bullets it shoots small cloverleafs.
I haven't pushed it yet...

Damn I wished you were closer. I'd like to chrono some loads in that. Nice stick you have there.

Nice article on CQB. (Close Quarters Battle)

http://wstiac.alionscience.com/pdf/WQV8N1_ART01.pdf

Interesting to note that the MK318 is not part of this.

To summarize the article, basically you need to double tap the target for best effect.

Another update...


It's too damn hot to shoot right now lol

I have about 300 rounds ready to fire. All different bullets and powder weights. I went to Lake City Brass from Remington Brass on the super High pressure M885 loads that Ramshot listed. I also changed primers from the Federal 205M (Been using the minimum safe primer so that I know CCI #41 will always be safe) to the CCI #41 for the 26.2 grns of TAC and the 62grn M885/SS109 pulled bullet.

I also mounted a scope on my Spikes ST-15 so we once the speeds have been accomplished, then the best accuracy at 100 yards and if time allows 200 yards for the different loads can also be established.

I can't wait until this heatwave passes.

Huh?

What twist on your 16" barrel.

Huh on what part?

1/7 twist.

Man that's a lot of numbers for a dumby like me. I've got a 1/9.
"Next was the homemade MK262 Sierra HPBT 77grn SMK using 24.4 grns of TAC.

20" AR -- 2750
16" AR -- 2600

I may go the full load of 24.8 grns to get the 16" AR more effective. I believe the factory loads for the MK262 call for 2750 FPS and I did achieve that goal with the 20" AR..but again it was hotter than u know what so my pressures were up plus I seated deeper to 2.255. These were accurate as ...you know what. Nice tight groups."

This is the part that interested me. Most 55 grain fmj won't shoot for nothing out of my gun. A 64 grain bullet does fairly well but I haven't tried heavier. But the twist rate is way different so . . .

You'll need a 1/8 twist minimum to stabilize the 75/77 grn bullet. You can shoot up to 69 grn usually depending on the gun with a 1/9 twist.

It's not really the weight of the bullet, it's the length.

You should be able to shoot 55 grain and 62 grain bullets with ease.

Do you have a 5.56 chamber and who makes your rifle?

Yes it's a 5.56 chamber. It's a CMMG gun. I can shoot the v-max 55 grain bullets fine. It's the fmj loads it hasn't done well with. The 62 and 64 grain stabilize well and are fairly accurate. I understand the length issue. Might I ask that if one were to use like an X bullet, with copper being less dense than lead and more metal (longer bullet) per equal weight bullet, would be a fairly accurate assumption?

I don't know the answer to that question. Perhaps somebody else can chime in on that.

I can say, and know for a fact that most XM193/Milspec/Nato FMJ 55 bullets are sub 4MOA lol.

The best group you will get will be with Hornady and they vary the least in weight. They are very well constructed bullets.

Midway USA is almost always out of stock of Hornady FMJ 55 grn because they are so good. You can get around an inch group out of those with H335 or TAC and other powders.

Standard milspec FMJ's are not accurate by any stretch of the imagination. If you can get under 2" you are doing well. It's not your gun....It's the ammo.

Yeah I figured that out when the plastic tip varmint bullets shot well with two different brands. Still, I wanted a little more substantial bullet for more than thin skinned varmints. I have a working load for now, but would like to work on it in the future. Some good info here to work with.

I had some Magtech small rifle 7 1/2 primers left over from 2008, when we couldn't find primers anywhere, and Cabela's had those in stock that I have been wanting to use up. I couldn't find the cup thickness listed anywhere so I started bugging Magtech for some answers.

I called MAGTECH and talked to a guy named John about the 7 1/2 small rifle primers and asked what the cup thickness was.

He had to call the factory Friday and got back to me this morning.

The Magtech 7 1/2 rifle primers have a cup thickness of .020.

So, it is NOT to be used in the high pressure milspec rounds. The factory that makes the primers for Magtech does make the thicker milspec primers but not for Magtech and they don't sell them.

So again, if you have Magtech 7 1/2 small rifle primers, do NOT use them in the 60,000 + pressure milspec rounds.

Strong work there sir!

Now could you please go through the same process for the 6.5 Grendel? Since that's what I'm going to rebarrel for.

Thank you!! I'm going to try to take next week off and get some of these questions answered for accuracy and loads.

If somebody wants to show up to the range with a 6.5 Grendel we can chrono and do some load development on it as well

I'm also in the process of working on the M882 9mm as well. Too hot to shoot so I've just been working on loading. I have some loads with Power Pistol, Unique, Blue Dot, and W231. I may make that a different thread because it can get complicated with the 115 and 124grn and super fast powders.

Anyhow....hopefully next week I can gather data each morning before it gets too hot, and settle on the most accurate best speed load for the different 5.56 rounds.