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Capt. mike
September 15th, 2014, 06:44 PM
Probably going to go dust off the presses and load up some 5.56 for a 10.5 AR upper.

Before I had just been loading for a 1-9 SS 16" and mainly was just using whatever powder I could find and going a hair over published .223 loads for 55gr FMJ.

Ive used IMR 4064, IMR4198, CFE223, and BL-C(2)

From my lee and hodgdon recipes cfe223 has the best velocity in a 50gr and is right behind varget for 55gr. This is a rifle recipe for a 24" barrel.

I also have a pistol recipe from hodgdon that is for a 15" barrel
this has varget at 2972 and bl-c(2) at 2816
also has H4198 (not IMR4198 which I still have a pound of) at 2719

the IMR4198 is the fastest rifle powder that I have and its nice as it calls for 20.4grs compared to the 27.5 for cfe or varget. Since this is for a 10.5 inch Im thinking that the 4198 would probably be getting about the same velocity in the short barrel as its burning quicker than the other slower powders.

I basically just want to load something that is optimizes for the shorter barrel that I can push a little on the hot side. Yeah I know 300blk works great for short barrels but thats what the vz58 and the AK are for. Oh yeah Im not worried about these being sub MOA just want to hold minute of beer can at 50 yards. I saw where the bbti guys chronoed remington UMC .223 55gr at 2616 in a 10" so I feel like with the right powder and loading it a little hotter I can get up to 27-2800 fps any thoughts?

Rumbler
September 15th, 2014, 08:56 PM
I'll do a little reading, but my intuition at this moment is telling me "probably H110/W296"


But it could well turn out to be 800-x.

You propose a tough nut to crack because it is not just a velocity issue. It is not even a gross pressure issue. Dwell time figures into this heavily as well, so you gotta get all three right if you want reliable function . . . . on more than just one single shot . . . ever.

Capt. mike
September 15th, 2014, 10:57 PM
I ran some 55 FMJ over 28grs of CFE223 all ran fine
Also had a few 55grs with 21grs of IMR4198 all cycled fine too.
Only hiccup was a hornady factory 55gr .223 but It may have been a mag issue. I tested with a mag of tula 55gr and that worked ok too.

Evil_McNasty
September 16th, 2014, 12:42 PM
Do people still use those pigtail coil looking gas tubes on their pistol builds?

Capt. mike
September 16th, 2014, 12:55 PM
I have seen them before but that sounds retarded, all the issues with pressure and dwell time is the gas port diameter and length its drilled at on the barrel, just making the tube longer by pig tailing it can only reduce pressure by putting more volume and heat loss in the tube. Unless it was for 16"s with carbine length gas that were "overgassed" and they wanted to soften the pulse.

Capt. mike
September 16th, 2014, 01:18 PM
Does anybody know of a site with any good information about this, every thing I can find says you'll shoot your eye out, to drive hybrid cars and to stop smoking.

Rumbler
September 16th, 2014, 06:34 PM
I've been doing some research on this.

To summarise what I have learned: "For long term reliable ar pistol functionality buy a 300 BLK". Every bit of data I can find for 5.56 pistol at the velocity the bullet needs to perform to specification is razor edge thin in terms of safety. +,- 1/10gr carries a warning to let someone you don't like test it first.

No shit.


. . and this from a guy that spent a couple of hours this morning putting 48.5gr of H110 under 240 grain pistol bullets. 8|

Capt. mike
September 16th, 2014, 07:39 PM
Well I had a 10" blk barrel but ended up getting rid of it. It was a pistol gas system that I guess is required for a 10-12". I know the 300 does better ballistically in a short barrel over 5.56 thats pretty clear, but given a fmj bullet out of either a 125-150 bullet out of a 300 isn't going to fragment either and the cost of components goes way up. I know you can buy ammo but its not at the price range yet that I can pile up enough ammo to be comfortable.

In a 10.5 upper green tip 62gr m855 runs 2612fps at 4 meters from the muzzle. Most people agree green tip frags above 2700 and may frag down to 2500. If you can get 2600 from a 62gr I feel like a 55-53-50 gr is gonna be in the frag zone up close and while expensive, ive seen some of those new barrier blind bullets that are made for 8" barrels. I know except for the bullets, barrel, and loading equipment most everything is the same but I just cant justify another caliber when I already have another AR and can use the ammo in both. I have plenty of rifles if I need a rifle, this is just a pistol and I don't expect it to perform the same as one of my rifles.

I completely agree, especially in a short barrel, the 300 is a better round ballistically, its also much more flexible especially if your running a can. But for me Im not sure its the best choice. Im more concerned with having ammo that pokes holes and runs than have a better round that I will have a finite supply thats not available. I like the idea that the 5.56 is still a bullet thats super sonic out a few hundred yards even out that short barrel and there is something to be said about cover fire and just because a bullet doesn't fragment in FBI ballistics gel doesn't mean bones don't explode violently when hit by bullet. I just think if it really did suck that bad why are special forces, DEA, and Navy boarding teams using the 10.3" Mk 18

Rumbler
September 16th, 2014, 07:50 PM
I just think if it really did suck that bad why are special forces, DEA, and Navy boarding teams using the 10.3" Mk 18

I understand.

But you should do some reading. The organizations you mention are not using 5.56 ammo you can buy on the open (legal) market. At least not at this time.

. . and remember that is the same logic folks use to justify the 9mm as a defensive cartridge, despite virtually every reputable source in existence labeling it "marginal at best".

Uncle stopped issuing small arms based on their actual effectiveness long ago.:(

It probably sounds like I am "arguing" my point, but really I am not. To each their own and I am fine with that. My interest (here) is in the discrimination of information and the furtherance of all our thought processes. :)

polebarn
September 16th, 2014, 07:54 PM
"Uncle stopped issuing small arms based on their actual effectiveness long ago.:("

Around 1962?

Rumbler
September 16th, 2014, 07:58 PM
I'm thinking a little before that. But that is a great example of the first theater wide issuance.

Capt. mike
September 16th, 2014, 08:04 PM
I guess what I'm asking is with just run of the mill FMJ is there really that much difference in a 300 to a 5.56. I love me some 7.62x39. But it suffers all the problems cited by 5.56 haters, it just punches holes too. Any of these will kill someone dead in one shot if its in the right spot but what advantage does the 300 have besides the fact that people love ARs and they wanted them to grow up to be an AK that they could dress up like a barbie doll.

polebarn
September 16th, 2014, 08:27 PM
Check out the wood on this one:

http://upload.wikimedia.org/wikipedia/commons/thumb/e/e4/M14_rifle_-_USA_-_7%2C62x51mm_-_Special_presentation_rifle%2C_Serial_No_0010_-_Arm%C3%A9museum.jpg/800px-M14_rifle_-_USA_-_7%2C62x51mm_-_Special_presentation_rifle%2C_Serial_No_0010_-_Arm%C3%A9museum.jpg

Rumbler
September 16th, 2014, 09:26 PM
As a guy with a well documented disdain for the AR platform in general, I can say what it is for me; the flexibility.

But . . .

1) I don't shoot run of the mill FMJ. Ever. I can't afford that and the performance is substandard.

2) With the same gun I can shoot 230gr bullets that hit like a ton of bricks so quietly you really don't need ears on even unsuppressed, to "AK-47 +P +accuracy".

But . . . admittedly the mechanical issues of the AR platform still exist.

Jafar kinda talked me into giving the AK platform a try - I know this is a coming out of the closet for me - but I like it. It is NOT as flexible, but undeniably it is a solid, reliable, combat effective weapon, one I could afford to feed factory ammo. I used to poo-poo all MBRs that didn't start with an M1 . . . but even closed minded 'ol SOBs like me can learn new stuff. :o


I guess what I'm asking is with just run of the mill FMJ is there really that much difference in a 300 to a 5.56. I love me some 7.62x39. But it suffers all the problems cited by 5.56 haters, it just punches holes too. Any of these will kill someone dead in one shot if its in the right spot but what advantage does the 300 have besides the fact that people love ARs and they wanted them to grow up to be an AK that they could dress up like a barbie doll.

Rumbler
September 16th, 2014, 09:29 PM
That wood gives me a woody. :roflmao:

The only way that could be prettier is if it was not so shiny.


Check out the wood on this one:

http://upload.wikimedia.org/wikipedia/commons/thumb/e/e4/M14_rifle_-_USA_-_7%2C62x51mm_-_Special_presentation_rifle%2C_Serial_No_0010_-_Arm%C3%A9museum.jpg/800px-M14_rifle_-_USA_-_7%2C62x51mm_-_Special_presentation_rifle%2C_Serial_No_0010_-_Arm%C3%A9museum.jpg

Capt. mike
September 26th, 2014, 11:57 PM
Ok I drug out the press and remembered what a pain in the ass reloading .223/5.56 was. I got a box of barnes 50gr TSX and loaded 10 once shot hornady brass up with a cci400 primer and 22.4 grs of IMR4198 (over max load dont try this at home) and went with the barnes numbers at 2.19 oal with a light crimp. I was gonna push it a little hotter but I figured I would pretend to be safe with these, Ive used close to 23 grains with a 55 grain but the primers were showing so Ill see how these do.

Rumbler
September 27th, 2014, 10:49 AM
4198 is still pretty slow for a long pistol length barrel, but the muzzle flash (or lack of it) and fired primer condition will be the best indicator whether it is too slow, just right, or too fast.


Please do try and remember to post your results, I'm all about learning stuff. :)

Capt. mike
September 27th, 2014, 01:20 PM
Yeah, I really wanted to load a couple with cfe223 just to compare the fireballs, but TSX bullets are almost $1 per just the bullet and only having 50 right now I just want something I'm comfortable with to have a 30rd mag of them loaded up. I think SR4756 would be a good powder as its on the slow side of the pistol powders and Ive got plenty on hand but I have no idea of a safe starting point. It will probably be monday before I can try them but Ill let y'all know how they do. Ive still got 50-60 cheap 55gr fmj I could play with using the sr4756 but If anybody can get some intel on where to start Id love to start work on some.

Capt. mike
September 30th, 2014, 05:56 PM
Ended up grabbing some 77gr otm gonna try and get close to mk262. Should be able to get out tomorrow and test them out of a 10.5", 11.5", and a 16"

Capt. mike
October 1st, 2014, 06:19 PM
Finally got to touch off my new loads in the 10.5" and didnt blow the gun up.

Both loads are over max so don't try this at home.

Barnes 50gr TSX
CCI 400 SR primer
22.4gr IMR4198
2.18 OAL
Lightly crimped

All I had was some plastic bottles with water but they were explosive, it was slightly overcast but still daylight but didnt have a lot of blast or flash, they felt hot compared to LC XM193
Couldnt find the bullet went though the bottles with a dime sized exit and grazed the 2x4 behind it.
Brass looked fine but the primers were just slightly flattened but I'm comfortable with it.

Next was the 77gr SMK OTM
CCI Mag SR Primer #450
25grs CFE223
2.26 OAL
Light crimp

Just shot these at cans and chased them down to the 50 yard line. I cant say what they would do on impact but they felt authoritative and you could definitely feel the difference in recoil. Brass and primers looked fine and flash and blast wasn't bad either, I really like these and the bullets were half the price of the TSXs. Ill probably load a lot more of these but I really want to run these on a chrono and see where they are at velocity wise.

Tack Driver
October 1st, 2014, 08:28 PM
The 77s are going to be the most consistant performers on impact at slower speeds. There is no comparison with 55gr, even as good a projectile as the TSX.

Capt. mike
October 1st, 2014, 09:49 PM
Yeah I'm going full retard on the 77s

e.money83
July 9th, 2015, 06:39 PM
So, hate to be the guy that drags up the corpse of a thread, but did you ever get around to running those 77s through a chrono? Trying to get an idea of how I should reload for a 12" barrel ar15 to try and keep as much energy on the round as I can, considering the velocity loss of the shorter barrel.

Capt. mike
July 10th, 2015, 08:02 AM
12" actually isn't that bad. M193 should hit the fragmentation threshold out of a 12 although not very far out. 75-77gr will do well whatever the barrel length

Capt. mike
July 10th, 2015, 08:04 AM
I never got a chance to chrono any of mine but the first batch felt more like i was shooting 20ga slugs than .223 so I backed down a hair but Ive got a mag full im wanting to try out on a chrono and see what they are doing

e.money83
July 10th, 2015, 08:11 AM
Awesome. Thanks for the update. :headbang:
Had to back it down, Ehhhh? Hrrrmmm. They were thumping you that hard, huh? We need to gel some of these fuckers and see what they do in a flesh like medium.

NJC
July 10th, 2015, 08:23 AM
Keeping in mind that I havent loaded this yet.

I am working with a buddy of mine who is a very experienced reloader. I am gathering the pieces for an MK262 mod1 clone round.

Lake City Brass
CCI #41 primers (for 5.56)
I just bought 1000 of the 75 gr bullets from dale because I could not find 77gr Sierra OTM to fit my budget, so I lose 2gr in weight there.
Powder : XBR 8208 it's temp stable and many 10.5 shooters have good luck with it.

I will be shooting it out of my DD MK18 upper 10.5 inch 1/7 and I will push it close to max. Cant say what that will be but will publish when its done.
I have to get some more powder and a few more primers to make the road trip to my buddys house/range an all day load, chrono, load day and hope to come home with 1000.

e.money83
July 10th, 2015, 08:45 AM
Shit yeah, keep me posted on that. I'd like to know how those preform aswell.

NJC
July 10th, 2015, 08:49 AM
Emoney.. will do. Have not forgotten about you,ben out of pocket for a couple weeks. You will have something inbound in the near future.

e.money83
July 10th, 2015, 08:58 AM
Awesome sauce:cool:

I know how it is to be strapped for funds all to well.

NJC
July 10th, 2015, 09:04 AM
/ inego montoya/

I dont think that means what you think it means


/inego montoya/

e.money83
July 10th, 2015, 09:05 AM
Quarterback reference, then?

NJC
July 10th, 2015, 09:10 AM
i was unavailable, out of town.

but out of pocket goes much better with us operators ;-)

e.money83
July 10th, 2015, 09:23 AM
5472

Capt. mike
July 10th, 2015, 10:22 AM
NJC let me know how that recipe turns out I got 1700 of those 75grs that need to be loaded up

NJC
July 10th, 2015, 10:39 AM
hope to know here in the next month or so.. will keep you posted.

Capt. mike
July 15th, 2015, 09:06 AM
Loaded up a few mags of the 75gr last night used CFE 223
Max load was 25gr with a 75gr vld bullet at 2.25. I went ahead and bumped the charge to 25.5gr as I have gone higher with the 77gr smk before, threw a light crimp on them and painted the tips with black nail polish to tell the difference between the 75s and my m193. Ilk try and touch a few off and see how they do

Rumbler
July 15th, 2015, 09:22 AM
'probably don't need to tell you to be damned careful. That VLD sticks way down inside the case to get a C.O.A.L. of 2.25.

I won't pretend that a compressed charge is 'death waiting to happen', hell I load a lot of compressed charges. But once you get to that powder touching the bullet point even as little as 1/10gr can make a disproportionately big difference in pressure. Ultra consistent charge weight measurement needs to be the rule of the day. :thumbup:

Capt. mike
July 15th, 2015, 10:28 AM
Im running these in a 16" and honestly I dont really need the extra 1/2 gr but im in the go big or go home mindset and Ive used a heavier charge with the 77smk which are slightly longer so I feel safe with the load but I know pushing past max 223 loads things can escalete quickly. I want to duplicate the tap 5.56 load rather than the weak .223 tap which from what ive seen is down 150~fps from the 5.56

e.money83
July 15th, 2015, 01:09 PM
I don't know much about reloading, (I've read a lymans manual from 92, and a hood bit of the materials available here and there) but that sounds scary as Fuck from everything I've read. I think I'd have to back that shoot down a notch and work my way up to what was comfortable/effective in my gun.

0utlaw
July 15th, 2015, 01:15 PM
Fat fingers on phone sorry

Capt. mike
July 15th, 2015, 01:43 PM
I don't know much about reloading, (I've read a lymans manual from 92, and a hood bit of the materials available here and there) but that sounds scary as Fuck from everything I've read. I think I'd have to back that shoot down a notch and work my way up to what was comfortable/effective in my gun.
the lawyers for the reloading companies make sure it does scare the fuck outta you for a reason because 10+1 might equal 50 and small fractions can increase pressure exponentially. That being said Ive found that there is usually room for improvement above most published loads. If I ever have the money to blow id like to do a "run it till it blows" to see just how far you could push loads to the point it blows the gun as they are designed to handle more than they are rated for

Rumbler
July 15th, 2015, 04:47 PM
I don't know much about reloading, (I've read a lymans manual from 92, and a hood bit of the materials available here and there) but that sounds scary as Fuck from everything I've read. I think I'd have to back that shoot down a notch and work my way up to what was comfortable/effective in my gun.

Your approach is reasonable. I won't recommend doing anything else.

But as one who has a preference for and a reputation of pushing projectiles far beyond "book" standards, I'll share the process I use to get there. Do not for one millisecond perceive the following as a recommended procedure, or as safe.

I'll take a load from a book, and try to validate it against other sources (other books). Look at the chamber pressure numbers (there is no direct correlation between PSI and CUP!) and compare them to the published ratings for the barrel, and often action of the firearm, I want to load for.

I'll base my starting load on pressure, not powder volume. If a "max listed load" is near the pressure rating for the barrel/action I'll use the listed load as a starting point. If the listed load is not near the pressure rating of the firearm I'll add a 1/10 or two of charge weight and make five or six rounds.

I'll take those cartridges and fire them paying close attention to the weapon itself. You can feel when a firearm is 'being a slouch' and when it is 'struggling to contain'. Then I'll police up the cartridge cases, put on my spectacles (or even better get a magnifying glass) and very very carefully examine the case for signs of overpressure and underpressure.

If there are NO SIGNS of overpressure, I'll go add 2/10 grain of charge weight to five or six more cartridges, and repeat the examination. I'll continue with this load/fire/examine/ process, backing off to 1/0 grain increments as the primer begins to show breach face imprint. As soon as I see the breech face imprint, and the shoulder of the primer flatten noticeably, I'll stop and call it good.

Yes, that very much DOES mean changing primer brands, case manufacturers or powder lots, can screw up the load data. That is exactly why once I find my happy load I'll make as much of it as I possibly can "all in one sitting".

This process is not flawless. Fortunately the worst repercussion I have had so far has been a significantly bulged barrel on a S&W 14-4 .357 magnum revolver. The barrel looked like a snake that had swallowed a football.

On the other side of that coin, compare these numbers to your load manual, I have learned that I can push a 250gr lead bullet 950+FPS out of a 1911, My 180gr 10MM load zips along about 1450FPS, I've got a 140gr .308 load that runs along over 4000 FPS, a .270win load topping 4500FPS, last . . and least ( ;) ) a 5.56 55gr load that runs 4400-4500FPS out of a 16" barrel.


The energy delivered to the target on all those loads far far exceeds what "should be". And ain't even in the ballpark with published load data.

e.money83
July 15th, 2015, 04:56 PM
Good...fucking...god...

Capt. mike
July 15th, 2015, 06:02 PM
That 4500 fps 55gr load what pressure is that at

Rumbler
July 15th, 2015, 06:50 PM
That 4500 fps 55gr load what pressure is that at

I do not have a proofing setup. But with a published maximum pressure for the 5.56 NATO cartridge at 62,366 psi, I'd say it is a safe bet I am probably there plus a little because I use a heavy barrel (as opposed to a standard "military" barrel.

I know that you know the 5.56 NATO cartridge will often flatten the crap out of the primers. My load only occasionally flattens a primer and I believe that is because I use exclusively once fired NATO brass and some primers seat more firmly than others.

Capt. mike
July 15th, 2015, 08:13 PM
So an AR in 5.56 is rated for around 62,000 psi assuming a normal mil spec barrel what is the typical point of failure assuming its an over pressure cartridge? I would think the bolt lugs or is it the actual chamber, barrel, primer, casing, ect given there is no bore obstruction

Rumbler
July 15th, 2015, 09:01 PM
Based on what I have read the most common thing that usually happens is bolt failure. It shears the little locking nubbins off.

Rumbler
July 15th, 2015, 11:31 PM
That is because you are ARMY. They give you guys the watered down version so you don't hurt yourselves.

;) :roflmao:;)

Capt. mike
July 19th, 2015, 11:13 AM
I tested mine out and like I said they should not be considered safe as they are over max loads but with 25.5gr of CFE 223 the 75gr hornadys averaged 2692 FPS out of my 1/7 twist 16" upper. Luckily I ran into mapper and he was generous enough to let me put his chrono in harms way. The primers were getting flat and I plan on bringing the next batch down a bit and using a thicker primer as well. Another note on the load when fired from a sar3 5.56 AK with no muzzle device there was no visible muzzle flash as opposed to the 55gr tula that had a very loud and visible fireball when fired in the same gun so I think this would be a good load for shorter barrels

e.money83
July 19th, 2015, 12:02 PM
wuufff...

Jmoorewar
July 19th, 2015, 03:35 PM
Do people still use those pigtail coil looking gas tubes on their pistol builds?
There a waste of money.