AR-10 Cast!!!

[x101airborne]

OK, Instead of standing on someone elses shoulders, again, I have started load development for the AR-10 in 308 Win. I am using Federal match brass full length sized with a .309 sizing button meant for the 7.62x39. I am using Wincester large rifle primers and unique powder, just for a start point. My first load was 12 gr. Unique with a 2gr. dacron filler. Lyman 311466 160 gr. Seated at 2.575 inches. 5 shots at 30 yards went 1 1/2 inches. Loads would break the bolt over, but not cycle the action. Not really thinking Unique will serve my needs, I think H-4895 will be what I try next. It is a really stable powder that can be loaded fairly light (Hodgdon recommends H-4895 for the reduced jacketed loads).

Stay with me, as I try new things, I will update posts. If anyone has a suggestion, please comment. When I get a BINGO, yall will be the second to know:bigsmyl2:

[Moonie]

I'm pretty sure you will hit max pressure before you will be able to cycle the action. It is a gas volume issue. You must use a slower powder to create the gas volume at the proper pressure at the port. Unique will peak way too soon, before the port. By the time the boolit passes the port the pressure will have dropped and the volume will be on its way down.

As I mentioned before, H4895 is a great powder to start with because you can reduce it by 60% safely.

[x101airborne]

Well, tried same everything but switched to H-4895 powder. First load was 25.0 gr wich would cycle one out of 3 shots. It also gave a nice little 3/4 inch 5 shot group with no leading. Next load was 30.0 gr of H4895. Looked like i hit that target with 000 buck. No semblance of a group. Barrel is now smooth with lead. It may be till tomorrow when I get that barrel cleaned and back to shooting.

[x101airborne]

Wish I had some H-380 to try.

[prs]

Well, tried same everything but switched to H-4895 powder. First load was 25.0 gr wich would cycle one out of 3 shots. It also gave a nice little 3/4 inch 5 shot group with no leading. Next load was 30.0 gr of H4895. Looked like i hit that target with 000 buck. No semblance of a group. Barrel is now smooth with lead. It may be till tomorrow when I get that barrel cleaned and back to shooting.

Now I have never done such a thing, so I am a totally ignorant commenter :bigsmyl2: , but why did you up the charge so much when 2 out of 3 cycled and group was only 3/4" with 5 shots (I suppose distance was still short). Why not up the charge 1gr at a time and then tweek in fractions of gr. In case I ever do get such an experimenting bug. ;-)

prs

[x101airborne]

Dont feel bad, im a totally ignorant expiramenter. That load would only cycle ONE out of three times. I really think that the one was more of an accident than anything. I suppose it was hasty to up it 5 grains at a time, but I was looking to see if accuracy would fall off first or if leading would occur. I guess both. Lyman listed IIRC 40 or 44 grains as max, so I thought I was good to go at 30.

[NSP64]

Your only as good as your lube and alloy

[mpmarty]

My 7.62X51 Saiga AK does just fine with a 170gr LEE boolit over 25gr of 2400 and a LR primer. Functions reliably and shoots into 3" at a hundred yards strings the shots vertically.

[x101airborne]

Funny you should mention that.... I was just looking through some recipies for a harder but malleable alloy. I would like to use this rifle for some limited hunting. Hogs, coyotes, etc. Not that I dont have other weapons that would work just as well. My current alloy is similar to lyman #2 air cooled. My lube is rooster jacket. Boolits are sized to .310.

[x101airborne]

If your 7.72x51 strings vertically, try adding some dacron on top of your powder. I have heard this controls stringing with cast loads.

[rockrat]

I don't think Rooster Jacket is for the kind of velocities you are looking for. I would use thinned LLA first, before you give up. I shoot 30gr of surplus 4895 in my Garand with no lead at all, but I use LBT soft blue lube too.
Try the LLA first.

Keep us informed, as I have an AR10 that I also want to use with cast.

[x101airborne]

raockrat..... i am far from giving up, i just have to do some serious cleaning :holysheep

What type of alloy are you using in your garand? I dont think this is any different than loading for the m1 Garand, M1A, FN-FAL, etc.... I think I am coming to a point that the easy rifles are loaded for, and to achieve what i want to achieve is going to take some different disciplines than what im used to. But... I no skered. I just need to do some basic one variable at a time testing. My alloy currently is soft. Gives great performance in bolt guns. This is not a bolt gun :groner:. So, with a little tayloring of load, alloy and lube (possibly a different boolit, maybe a 170 gr.) I think i can getter done.

[NHlever]

raockrat..... i am far from giving up, i just have to do some serious cleaning :holysheep

What type of alloy are you using in your garand? I dont think this is any different than loading for the m1 Garand, M1A, FN-FAL, etc.... I think I am coming to a point that the easy rifles are loaded for, and to achieve what i want to achieve is going to take some different disciplines than what im used to. But... I no skered. I just need to do some basic one variable at a time testing. My alloy currently is soft. Gives great performance in bolt guns. This is not a bolt gun :groner:. So, with a little tayloring of load, alloy and lube (possibly a different boolit, maybe a 170 gr.) I think i can getter done.

I'm assuming that the Garrand is a 30-06, and there is a lot of difference between 30 grains of 4895 in a .308 than 30 grains of 4895 in a 30-06.

[NSP64]

X101 is the leqd from the chamber to the muzzle. If it is it is an alloy failure. If it starts down the baarrel a ways , then its lube failure.

[rockrat]

Nope, Garand in 308. Even 28gr works well, but accuracy was a bit better with the 30gr load (165 RCBS sil boolit). I was using water quenched , ww/lino in a 4/1 ratio. Sized .311"

Working with a Handi Rifle now and a Rem 700, but AR10 is next

[x101airborne]

Nope, Garand in 308. Even 28gr works well, but accuracy was a bit better with the 30gr load (165 RCBS sil boolit). I was using water quenched , ww/lino in a 4/1 ratio. Sized .311"

Working with a Handi Rifle now and a Rem 700, but AR10 is next

See.. I was thinking about taking 5 pounds of my #2 recipe and either water quenching (most probable) or adding 1 pound of lino to the mix and re-casting.

Just for clarification, the lead is ALL the way down the barrel. ALL, the way. I took it to mean an alloy failure. ALL the way down. The whole thing. Stem to stern. Breach to crown. End to end. The whole enchilada. you get the idea.

[Dutch4122]

The alloy that you are looking for is 50% Wheelweights and 50% pure lead, water dropped from the mold. Size, lube, and gas check them within 24 hours of casting. Let them age for 2 weeks and they will come out to a BHN of approximately 22. This alloy is hard, but malleable and works very well for high velocity with cast boolits.

Hope this helps, :D

[x101airborne]

Dutch, that is just what I was looking for!!! Excellent help. Thanks.

[Dutch4122]

One other thing, a good lube is mandatory when you are trying to go fast. I recommend either Carnuba Red or BAC. Both of these lubes are made and sold by a member here that goes by the handle of "Lar45." You can look him up on the members list above. Check out his website and decide for yourself which of those two lubes will serve your needs best. Also, Glenn's prices can't be beat, as his lubes are less expensive than RCBS or Lyman lubes. With both of them you will need a heater on your lube sizer.

As for powder selection. If you were shooting a bolt gun I'd be telling you to pick a slower burning powder. Possibly even slower than 4895. I have had good results with IMR4007SSC and a 210 grn slug in a 16.5" barreled 7,62x51 Milsurp bolt action. The reason for this is to not overstress the alloy before the boolit leaves the barrel. The problem you have, and one I have no experience with, is that you have to match your gas volume pressure at the port like "Moonie" mentioned. Which slower powder will do that and still give the velocity you want while cycling the action is something you'll have to experiment with and find out for yourself.

Edit: You might want to PM "357maximum" here on the board. He is shooting the BRP 30-180-SIL Modified out of a 20" barreled 7.62x51 Spanish Mauser at full jacketed velocities. I believe he is loading with powders in the 4064 burn range and it may in fact be Varget that he is using.

Ain't Cast Boolits fun?! :brokenima

Hope this helps,

[gds]

I worked on a .308 load for my L1A1 based on Bruceb's thread, using reloader 7, because that is the powder I had on hand, and Lee C312-155-2R. Got to 29.5 grains and would function the L1a1 100% and no leading. Accuracy was good enough for plinking.

[x101airborne]

Thanks to all who reply. I am heat treating 50 boolits right now and will dip em in 50/50 alox for lube just to try. I am very excited to make this work.

[x101airborne]

So day two of testing. Same load as before. 30 gr H-4895 but with the heat treated boolits. Loaded up 5 with 1.0 gr dacron and 5 without. The dacron load shot fairly well (1 1/2 inches at 30 yards), but smoked heavily. The plain load did not smoke but did not shoot as well. The heat treated boolits worked much better. Barrel is shiny and clean. Bad news is i am almost out of checks. Dang it all.

[mike in co]

since the ar10 is a mil gun...why not go to the mil cast boolit forum aqnd look what was done with the m14/m1a ??
this is the second time i posted this..the first went ????

yes the ar10 was an issue arm to the portguese and the sudanese.....the current armalite ar10 is a "b" model......ohhh and rockriver ,bushmasters, remingtons are 308's...not ar10's....

then there are sr25's( what happens when you take the best of an ar15 and add it to the best of an ar10 ??? you get an sr25!)

mike in co

[x101airborne]

Mike, it sounds like you know your stuff. I never knew anyone but us troops were issued AR-10's. Still, I dont understand the difference between what you are calling a 308 and what im calling an AR-10. I am looking at some of the ideas done with the m14 / m1a, but some qestions such as water dropped or air cooled, seem to be vaguely answered if at all. Also, i do not remember where the gas port is located on an m1a, and I think the pressure curve of the powder charge, the size of the gas port, and the pressure needed to operate the gas system may all be different variables specific to this type / style of rifle. Maybe some would disagree, but it seems worthy of consideration.

[x101airborne]

Just finished round three of testing for today. I stayed with 30 gr. H-4895 because it was as low as i could go and cycle the action. I went with the heat treated boolits and varied the seating length. I tried lengths of 2.635, 2.610, and 2.575. 2.635 was about 4 thousandths into the lands and would not allow the bolt to close reliably. 2.610 functioned well and grouped 6 shots under an inch at 30 yards. 2.575 grouped well, but not as tight as 2.610. On a side note, if I slammed the bolt on the 2.635 rounds, three went into one tight hole with two flyers opening the group to around an inch. With this being an autoloader, function is a must, so this load is out. When I get more gas checks, I will resume testing.

[mike in co]

if you are shooting 3 inch groups at 30yds(9in at 100)....i would rethink my approach....

i shot 174's at 1700 at one of the earlier winniemuccka shoots....i shot under an inch at 100 and was beat by 45nut shooting my ammo in my gun......

mike in co

[x101airborne]

if you are shooting 3 inch groups at 30yds(9in at 100)....i would rethink my approach....

mike in co


????????????????????????????????????????????

Im shooting one inch at 30 yards. Yeah, if i was shooting 3 inch groups at 30, i would go back to jacketed. Better yet, send the rifle back.

[Just Duke]

I have two AR-10's left. Standing by.

[BruceB]

[QUOTE:
" some qestions such as water dropped or air cooled, seem to be vaguely answered if at all."

Vague? Vague? After a quick look through that thread, I'd bet there are AT LEAST ten places where I stated that the bullets were water-dropped wheel-weight alloy.

Again, for the record:

ALL were water-dropped.

-ALL were cast from my WW alloy.

-ALL were sized at .311"

-ALL were cast using my particular method.

-ALL were cast at the maximum temperature my RCBS furnace can deliver (870 degrees F).

The project was already unwieldy enough, without adding complications such as different alloys, casting temps, sizing diameter, etc.

The permutations approach infinity if every possible variation is to be tested.

**************************************************

Gas-port positioning, from bolt-face (approximate, but close):

M1A: 14"

AR15 (not AR10 but similar layout): 13"

DSA FAL: 11"

[NHlever]

I've gotten some surprisingly good groups from my .308 bolt gun lately with 29 grains of IMR 4227, and the Lee 150 FN. I'm not familiar with the AR-10, and don't know what gas volume a load like this will give you, but it might be another path to explore. My groups are running an honest 1/2"-3/4" for five shots at only 50 yards, but things are looking good so far. (100 yard butt was pretty snowed in)

[Larry Gibson]

Since the AR 10's gas system is designed to function with standard NATO spec ammo I can see where it would pose any reloading of cast bullets any different than with the M1A/M14. About the only thing Bruce and I do different is I most often use an AC'd alloy of 16 - 18 BHN instead of WQing WWs. Regarless, our results are pretty much the same. I have used my loads with 311291, 311466 and 311299 in a couple AR10 rifles and an original AR10 made for the Portugese.

I suggest you follow Bruces information as it will get you there with minimal fuss. If not then try the 311299 over H4895 (start at 25 gr and work up in 1/2 gr increments to 30 gr) and use a 1/2 gr dacron filler. I use Javelina lube which is a 50/50 NRA formual lube or Lars equivelent. I get no leading upwards of 2600+ fps (311466) and excellent accuracy. That load will give you very good results from M1A/M14s, FN/FALs, G3s and AR10s along with bolt actions. You probably have a 10" twist barrel so work up until functioning is reliable and velocity does not get over 1950 fps. for best accuracy also. No sense in reinventing the wheel unless you feel obliged to do so. Bruces info is very good and applies to Your AR10 as well.

Larry Gibson

[mike in co]

what larry and bruce said...........
unless you have time/money/lead/powder to waste.........

mike in co

[x101airborne]

So I wasted some time/money/lead/powder...... Now I didn't really know wich way to go after the H-4895 failure. So I decided to try my next powder faster and my next slower. The slow one first. RL-19. If 30.0gr of H-4895 was near optimal, I figured that 30.0gr of RL-19 was a good place to start. 30.0 gr was loaded in 5 winchester neck turned cases. When fired, the barrel had quite a lot of unburned powder in it, but the group was only 1.5 inches wide by 6 inches vertical. I worked up in one grain increments firing 5 shot groups of each charge. Accuracy started going down at 33.0 gr. The good news is 32.0 gr gave a 1.5 inch group total. Three shots made a group less than two boolits wide. The other two were just outside of that by about .6 inches each. Unfortunately still not enough pressure to lock the bolt back. I was single feeding with a dead mag in the well. We just had a norther blow in here so testing is done for today. As soon as I can get back to it, I think I will test different amounts of dacron filler. Should be able to get this down to a functioning one hole group.

[jimr]

i have had very good results with IMR4831

[mpmarty]

Give some thought to BLC(2), it works well for me in my 308 bolt gun and functions the 7.62Nato AK smartly.

[Dutch4122]

RL-19 is probably a bit too slow burning for your application. That's why you had the unburnt kernels in the bore. I would try something in a faster burn rate. My gut is telling me your going to find the sweet spot somewhere in the 4064 to 4350 range; and you'll be able to do it without fillers.

Just my 2 cents,

[x101airborne]

Hmm. BLC-2, IMR 4831, and dutches' range of 4064 to 4350. I will give these a lookup as I have most of these lying around. I am concerned with clenliness of burn, with it being a gas operated weapon.

[Dutch4122]

......................... I am concerned with clenliness of burn, with it being a gas operated weapon.


As you get into faster burn rates you will see a "cleaner" burn. Shorter barrelled rifles (I'm assuming yours is 20") will be able to use faster burning powders without overstressing the alloy before the boolit leaves the barrel; and it works just the opposite as you increase barrel length.

I'm very anxious to see your results with faster burning powders in the range I mentioned previously.

:popcorn:

[x101airborne]

I did not realize I skipped so far down the burn column fron 4895 to RL-19. Skipped over a lot of good powders. Varget being just one.....

[rays308]

First post but, I had to jump in on this one.
The AR10 was my last summers project and the one that brought me here.
I used powders from 4227 to 4831sc and was able to get my AR's to function and shoot straight.

Settled on Varget, 4064 and 748. I'm planning on working with BLC2 this year.

BruceB's article is definitely the place to start. After you read it, read it again, then again. He did alot of foot work for you.

I have 20in and 16in AR's. The gas ports are spaced differently on each however, I didn't have much problem getting the loads to work in both. I worked up the loads in a shorty and added maybe a half grain to get the same functionality from the 20s.
Dacron didn't seem to matter much in my AR's. I think I got less smoke using dacron though.

Water dropped WW are a must. I have run the 180gr lee to 2600fps without leading.
I tried the heat treating but, found I didn't need to. I havent had leading in any AR10 yet.

I started with a Lyman 311332. It was a pour choice for me. After all the lapping I had to do to get it round, it made a better 303 bullet than 308. Its now a jacketed mold.
I also played with the lee 200gr. I think it has too much nose, it wasn't as reliable as I would like in the 20in.
The 180gr Lee was better but I settled on the 160gr Lee. Overall the 160gr works best and gives me better groups.

I like some lube on the nose of my bore riders. I lightly tumble then gas check and size to 309. Then I dip in LLA and let stand overnight.

I liked my mouse guns but, AR's in 308 rock for me. The 180gr bullet at 1800fps has more energy than a 223 55gr at 3200fps. It gets there slower but with more authority.
The lighter recoil is nice to. With lead bullets the AR10 is good to 200yds easy.

If you haven't already, you might want to polish the feed ramps and do away with any sharp edges that might shave the lead. when the sliced lead gets around the case the bolt won't close all the way and its a real bear to get open. I first had this problem with ballistic tips years ago on both AR10 and ar15.

Have fun with finding your loads, it will work I shoot them all the time.

Ray

[sqlbullet]

BruceB's article is definitely the place to start. After you read it, read it again, then again. He did alot of foot work for you.

This....

Starting with BruceB and BobS work I have never had a 'bad' load from my Garands. I have had OK, and I have had really good.

[edward hogan]

Why neck turn?
Only reason to turn necks is for benchrest chamber.

Probably more critical to hold oal of sized cases to within .003" (or maybe less if only own one semi-auto 7.62x51mm). Take Wilson case gauge or RCBS Precision mic and verify OAL of fired brass, then size to minimum necessary to reliably seat the round. .003" reduction from fired case OAL is good place to start.

After reading Bruce B's thread on loading for his M1a, I am definitely going to pursue for both my SA and Armalite. Have bought rifle molds over the years just to be sure I had bullets to shoot under worst case scenario. Now am becoming a believer that cast may actually be Best Case Scenario!

My .30cal bullet is the Lyman 311332, still new in box. Have plenty gas checks and Lyman 450 w/sizer. Have one of those Armalite Eagle Arms 24" cm triple-lapped match barrels that might just be the perfect cast platform, along with 16" chrome-lined and an M1a w/TRW chrome GI barrel. Lots of wheelweight ingots and a number of powders. Guess I'll see how Lyman 311322 does when cast from WQ WWs and GCed.

Very encouraging and exciting to have access to this information and all the guys who are pioneering the data.

Actually have toned back my shooting in recent years other than minimal load development because just don't have the time to clean the bores once done. As I am not a velocity slave, the cast bullet venue looks ideal for me.

Thanks VERY MUCH to all you pioneers and hope to contribute some meaningful discoveries of my own soon.

[45 2.1]

A different approach than what you've read before. Try Surplus 7383............ its a triple based powder and is out there from three different powder lots. I've worked with it in cast and jacketed in most of the 30 caliber military rifles. I started trying it in the 308 some months ago thinking it would be too slow. It was with less than 100% density giving vertical stringing. At 100% density (that is a full load with powder to the base of the neck measured by a B&M powder measure) that changed. Make sure your cases are all the same capacity as different lots and types effect results drastically if you mix cases with the same powder charge. With a full case, a BRP 180 gr. Silohuette boolit from 50% PB / 50% WW water dropped, aged a couple of months, and sized 311" with my own lube and Rem 91/2 primers, it gave long range groups (378 yds ) of about 1/2 to 5/8 MOA. This is out of a AR-10 with 20 inch barrel BTW. In some bolt actions it wasn't worse than 1.5 MOA. It is a healthy load that expands the case as well as military ball and cycles the action properly. Hard to believe, isn't it........... But these got witnessed by a couple of board members here........ they're going to buy that mold to. Give it a try............

[Lloyd Smale]

a 180 cast and 22 grains of 2400 ran my cetme

[x101airborne]

Again, neck turning was an exparament. I was concerned that my brass was being sized down tight and therefore sizing my boolit down. I was trying to gain uniform neck tension without squeezing the boolit down. That and with the oversized lead boolits, the thick necks seemed to hang in the rife chamber and gave some sluggish chambering where the last 16th of a tun of the bolt would not turn all the way. This gave me concerns about firing the weapon out of full battery.

Them bench rest boys are really good at what they do. But that does not mean I cant pick up a trick or two.

[rays308]

I turn mine to true them up. Especialy the mil surp brass. If the mouth thickness varies from side to side and I squeaze it into a round die, the variation is now in the inside of the mouth. When I press a boolit into the case the weak side will give before the thick side. Runnout is born.

Also, if the case mouth is too thick you get feeding problems like x101 stated above..

I think the 311332 is ideal for the autos. I use medium to slow burning powders with just enough to insure the action works.

Another good boolit is the Lee C309-160-R.

I have had a couple of the 311332s break off at the first groove when feeding. They were heat treated at 420deg so, probably my fault.

[AaronJ]

X101 if you have not tried varget yet, you should.

I took this

http://i760.photobucket.com/albums/xx241/aaron_454/IMAG0063.jpg

feed it these

http://i760.photobucket.com/albums/xx241/aaron_454/IMAG0088.jpg

and got this

http://i760.photobucket.com/albums/xx241/aaron_454/IMAG0071.jpg

at 100yds.

Load is 28gr varget in win brass pushing a NOE 311365 cast of AC lino sized to 311 lubed with a homebrew hard lube and a hornady check. Next time I get my chrony out I will try and get a velocity for them.

[x101airborne]

AaronJ,

That group reminds me of 1996 Kathy Ireland in a bikini. Awesome would not cover it. Congrats to ya!!! I have pretty much settled on Varget as my powder, now just playing with some alloys and heat treating. Then on to lubes!! You are very fortunate, Sir.

[edward hogan]

Got a custom barreled 10? Krieger or GA Precision, then maybe IF your gunsmith set it up for match chamber and borderline tightneck, then you might benefit from turning necks or need to; but have never heard of a .334 necked gas gun. The Armalite or DPMS factory chambers are mil-spec. Might see some benefit from reaming overly thick-necked brass but turning for match concentricity etc is not going to gain you much.

Cast some of the Lyman 180gr pts over the last couple days. These weigh out at 186gr w/o gas check and at about 189gr with. Cast from straight wheelweights, my bullets measure .3105" miked. These are unsized. Might not need to size these at all, but testing will tell.

I use Redding Type S FL sizer dies to control neck tension and always FL size for semi-auto, lever, pump etc. Can use a spacer under the die for neck only sizing for bolt rifle, more versatile than the S neck die unless you want to own both. Got a micrometer or caliper? Mike one of your unsized, fired cases and compare the neck diameter with a loaded round. Probably see about .004 variance fired case neck expanded over loaded round. Don't forget .001 brass elasticity/snap-back so a typical chamber is going to be .006 larger neck diameter than loaded ammunition, maybe .007 or more. How thick is that brass in the neck? Likely about .125 to .150 or larger.

Comment made about turning necks to reduce risk of failure to feed; unless I misunderstood. Wouldn't polishing or reshaping feed ramp to M4 profile on the gas block be better? There is no benefit from thinning the neck in a factory NATO spec chamber, so why open yourself up to reduction from minimal semi-auto brass life?

Might want to experiment with the David Tubb AR recoil spring and bolt carrier weights or an adjustable gas block to enhance operation if you have a dedicated-to-cast upper assy. Also consider the gas port diameter, might be worth trying a minimum opening to gauge any performance difference if you open-up the gas hole a bit.

[gvrj]

x101airborne where are you on this project? Find anything to work to your satisfaction?

[x101airborne]

Well, no. Not really. And to tell the truth, it has taken a back seat. I thought that since I was having some issues with the semi-auto's, I would back off to a bolt action and kinda learn the ropes.

See my thread "MOA with the 30-06". Some of my issues with the AR-10 (or whatever you want to call an AR in 308) is I want an appropriate shape boolit that expands on flesh for hunting, cycles the action, doesn't lead, and shoots MOA consistently. Wich is asking a lot for a semi auto rifle with a really short throat. And after working with my '06 and seeing what kind of spindrift I am getting at only 200 yards, I am not just real sure I want my AR-10 as a cast only rifle.

[gvrj]

Thanks for the reply. Let me go read that thread now.

[theTastyCat]

Sorry to bring back a 2.5+ year old thread, but it seems more logical to do this than to begin a new one.

I'm on a mission to find a good, practical cast load for my 1:10 AR10 that isn't a shadow of what j-word ballistics are. This thread is a newly discovered gold mine. I've done a great deal of research (with the kind help of many of you who have contributed to this thread) but this thread has blown the top off of several of my preconceived notions.

I've been laboring under the assumption that I'll need to stay somewhere between 1666 and 1944 FPS to satisfy the RPM threshold, but here I see you all pushing boolits even past 2600!! I knew the RPM threshold is more of a guide than a rule, but this changes everything for me. How is this possible? I'm particularly keen on boolit stability to keep from keyholing a round through the endcap of my suppressor. But the ability to basically replicate match jacketed 308 is incredibly enticing...so basically how are you all getting accurate loads that are that fast?? I seem to be receiving so much conflicting information...so how the heck is this possible???? Just the perfect combination of boolit and rifle? I would kill to get such a strong load for my rifle!! I'm gleaning everything I can from BruceB's M1a thread now but so much of this is still a mystery; already in this thread it's been cautioned not to exceed 1950 FPS for accuracy. Please teach me how to maintain stability and accuracy at these higher, more ballistically practical velocities!!! I've been considering trying to get as heavy a boolit as possible given that I wouldn't be able to drive them very fast, but this changes everything.

An extremely generous member here was kind enough to send me several of his powdercoated, cast boolits from his Lee CTL-312-160, and I'm quite eager to load them up and see what they can do; powders that I've been told are good contenders are Re7, 2400, H4895 and H4227, although I see may more mentioned now. Which of these, or another, would you all recommend? Especially that I'd love to get deep into the 2000s velocitywise if possible...

By the way, I will be powdercoating my boolits, which should give me more leeway in terms of alloy and will keep from fouling my suppressors as much. Have any of you all played with PCing yet?

This is incredibly exciting, guys - many thanks for all the work this thread represents!! This IS the best site on the net - incredibly helpful, friendly, and useful. You restore my faith in humanity!!

[winelover]

Been working on load development for my Armalite AR-10-4 carbine for the last eight months. I have a backyard range which allows me to shoot whenever I desire. Sent many combinations down range.

Powders that I have tried include SR 4759, AA 5744, AA 4350, AA 2520, IMR 4198 and Varget. I abandoned 4759, 4198 and 5744, because accuracy was going south, as charges necessary to cycle the action increased.

Boolits, that would reliably feed, were RCBS 165 and 180 SIL, NOE 311365, Mi-Ha's 180 SIL and Lyman's 311413. I tried some of these boolits air cooled, water dropped as well as heat treated. My alloy is somewhat close to WW alloy. Air cooled works fine with the lower velocities and either water dropped or heat treated for, higher. However, I have seen sightly better accuracy/consistency when heat treated.

I am currently working with AA2520 because I have a good supply of this ball powder. It will cycle the action with charges as low as 28 grains and do it with authority. I am looking at a 2 MOA, 12 shot group @ 100 yards, using 29 grains of 2520, CCI 200 primer, LC -08 brass and a water dropped 311365 boolit, sized on a Star (.311) with LBT Blue.

AA 4350 also gives me 2 MOA, 10 shot groups with 36.5 grains and a CCI 250 magnum primer, but with a heat treated 311356 boolit. These were lubed with Carnuba Red.

Varget is showing promise with Mi-Ha's 180 grain SIL. Again, 2 MOA 10 shot groups, 29 grains with air cooled alloy or 33 grains with water dropped. Lake City brass and CCI 200 primers.

I am striving for 1 MOA, which isn't a problem when shooting 5 shot groups. Ten shots or better, make a huge difference!

Would like to chronograph all the various loads I've tried, but is a PITA to set one up with a blast shield, that is necessary with the flash hider / muzzle brake that came with the carbine.

Winelover

[Larry Gibson]

winelover

What a refreshing post; realistic loads with sensible accuracy claims using the bullets stated. Thanks for the info.

Larry Gibson

[popper]

I pretty much stopped when I got here, LR-308 carbine, 165 gr LFN, HFPC H.T, H4895, LC MG brass.
110300
My shooting needs to improve. Oh, yes @ 100. 13 rnds in the circle.

[Larry Gibson]

theTastyCat.

......I've been laboring under the assumption that I'll need to stay somewhere between 1666 and 1944 FPS to satisfy the RPM threshold, but here I see you all pushing boolits even past 2600!! I knew the RPM threshold is more of a guide than a rule, but this changes everything for me. How is this possible? I'm particularly keen on boolit stability to keep from keyholing a round through the endcap of my suppressor. But the ability to basically replicate match jacketed 308 is incredibly enticing...so basically how are you all getting accurate loads that are that fast?? I seem to be receiving so much conflicting information...so how the heck is this possible???? Just the perfect combination of boolit and rifle? I would kill to get such a strong load for my rifle!! I'm gleaning everything I can from BruceB's M1a thread now but so much of this is still a mystery; already in this thread it's been cautioned not to exceed 1950 FPS for accuracy.

BruceBs sticky is an excellent reference for information and how to load for the gas guns. Your basic quest is one that most of us thought about, tried and still try to achieve. Come make great claims as to velocity and accuracy............try to reproduce those claims, if you can, is all I'll say about them. When you've completed that attempt and tired of it you'll come to accept the facts BruceB presents in his extensive tests.

An extremely generous member here was kind enough to send me several of his powdercoated, cast boolits from his Lee CTL-312-160, and I'm quite eager to load them up and see what they can do; powders that I've been told are good contenders are Re7, 2400, H4895 and H4227, although I see may more mentioned now. Which of these, or another, would you all recommend? Especially that I'd love to get deep into the 2000s velocitywise if possible...

By the way, I will be powdercoating my boolits, which should give me more leeway in terms of alloy and will keep from fouling my suppressors as much. Have any of you all played with PCing yet?

PCing your bullets will get you useable accuracy at higher velocity for sure. You will also want to use a harder yet malleable alloy that is HT'd to 28+ BHN. I found in test with PC'd bullets in an AR and a bolt gun that accuracy was better and more consistent at higher velocity (2500+ fps) when the bullets were also lubed. However, you may not want to use lubed bullets with the suppressor. If you don't want to get discouraged too soon don't get star struck over the accuracy claims. ARs can be good accurate rifles but there is nothing magical about them. Go for quality not quantity when you cast your bullets, use a good bullet design, use proper loading techniques for accuracy and use proper load development techniques for testing.

Popper can give you some good advice on making the harder and PC'd cast bullet and techniques.

BTW; If you want to push above 2000 fps with the 7.62 NATO using a cast bullet of 160 - 190 gr in your AR then 4895 is the minimal burning rate powder to use.

Larry Gibson

[Ford SD]

Would like to chronograph all the various loads I've tried, but is a PITA to set one up with a blast shield, that is necessary with the flash hider / muzzle brake that came with the carbine.

Winelover

Put your chronograph out at 15-18 ft it works and you get alot less faulse readings
BTW I either shoot over the chronograph or just shoot for groups never both at the same time

if you put a target app 2 feet behind your chronograph and put a target dot about 1 foot up you will not hit your chronograph
and I make sure when bullet goes through such a close target it hits the back stop

[winelover]

Put your chronograph out at 15-18 ft it works and you get alot less faulse readings
BTW I either shoot over the chronograph or just shoot for groups never both at the same time

if you put a target app 2 feet behind your chronograph and put a target dot about 1 foot up you will not hit your chronograph
and I make sure when bullet goes through such a close target it hits the back stop

My Master Shooting Crony is set up at the limit of cable supplied. IICC, it's at least 18 feet, if not more. Without a blast shield, all you get is ERROR readings. Cbrick brought over his deluxe chronograph, a PACT, I think. Same difference! The blast on this carbine is worse than my 338W Magnum!! Rick can feel the blast, sitting behind and off to the side.

Eventually, I 'll chronograph "my load" but for now, I'm concentrating on attaining that perfect combination.

Winelover

[theTastyCat]

And all of these new responses are simply further proof of why this is the best site on the net. Armed and dangerous with this new information, I forge ahead!!

One more quick question: at least theoretically, would a 170-gr. and a 200-gr. tend to lose accuracy at similar velocities, or would one generally tend to be more stable at higher speed? Before I get down and dirty I'm trying to figure out where the biggest bang for the buck will be ballistically.

Many, many thanks, all!!! Long live this fine forum.

[theTastyCat]

Gotcha, popper - I've made it this far messing around with pistols to not need antimony - I guess I need to see if I can find some!! I'm sure there's resources here elsewhere that will help me in my quest. I will happily pursue a lighter boolit! that Lee 160-gr. mold is looking better and better.

[cbrick]

My Master Shooting Crony is set up at the limit of cable supplied. IICC, it's at least 18 feet, if not more. Without a blast shield, all you get is ERROR readings. Cbrick brought over his deluxe chronograph, a PACT, I think. Same difference! The blast on this carbine is worse than my 338W Magnum!! Rick can feel the blast, sitting behind and off to the side. Eventually, I 'll chronograph "my load" but for now, I'm concentrating on attaining that perfect combination. Winelover

Actually it's an Oehler.

His rifle has some of the worst muzzle blast I've seen, even at 15 feet the start screen registers nothing but muzzle blast. No choice but to shoot through a blast shield which makes grouping very difficult.

Rick

[xacex]

I am going to jump in this thread. Just finished a LR 308 rifle, and have never loaded 308 cast outside of 300 blackout, 54R,x39, and 06. I would like to see what the Mihec 311410 does with 308. a 130 grain boolit will be hard to get slow enough to not obliterate yet cycle the action. If I cant get it to cycle I may be able to use a AR15 buffer spring to get it to work. So far I have got 2180 fps out of the blackout with this boolit, and it does just fine, but if I can get it going a little faster with the 1/10 twist, and better accuracy with 18" vs 16" I will be happy.

[winelover]

My very first foray into cast for an AR was with donated 138 grain Leadhead spitzer boolits. The results were, what pushed me forward. Not stellar accuracy but then I didn't expect that with commercial cast. At that time, I was using both AA 5744 and SR 4759 for load development.

AA 5744 would reliably cycle the action, in the neighborhood of 26 grains, but by then the groups were starting to open up.

The starting charge for SR 4759, was 20 grains, and it gave 1 3/4" groups but wouldn't cycle the action. I quit at 27 grains, still wouldn't cycle, and I was getting shotgun patterns.

Since then, I've moved on to slower powders and heavier boolits.


Winelover

[xacex]

I have been looking for some data to push the NOE 311-247 to the limit in the 308. The only data I have found with a bullet of that weight is listed in the Lee manual. It lists a load of IMR 4350 pushing a 250 grain bullet to a speed just over 2000FPS. I would rather use Varget, or H4895 which I have more of now, but that was all I could find for the powders I have. That data suggest that the PSI is approximately 56K which should cycle a 308 AR with gusto.

[theTastyCat]

Dang, popper - that is incredibly encouraging! I'm about to load some 168s in front of some H4895 - if you don't mind sharing, approximately how much powder got you there? I'm going to start safe but would love to know where you ended up.

[theTastyCat]

Gotcha - sorry, it's been a while! FINALLY got to load up today - they sure are pretty! Taking 10% off my Lee manual loads for 165 j-words, I loaded a few each of 37.0, 37.2, 37.4 up to 39. Have a few left over to push the envelope! This is incredibly exciting - I may actually be able to shoot all the .308 I want!!!! Man, what casting and PC has made possible...amazing. Once I get .308 figured out, it's on to .338 Spectre and 357SIG!! This is great. Something about being able to craft the most crucial part of the round oneself is incredibly satisfying; now if I could just find easy lead now that WWs are largely useless :(

[bruce drake]

Resurrecting this old thread as well. I just finished building an AR10 (DPMS/PSA pattern) with a 20" 308win barrel and I'm waiting for the bolt carrier group to come in the mail sometime this week or the next.

I hope to get out to the range shortly after that to see what I can do for operable loads based off this thread and my previous loads for my CETME. I intend to try several 30 caliber bullets as well. I have the following 30/31 caliber molds to experiment with:

Lyman/Ideal (all sized at .310)
311359 (115gr spitzer gas-checked)
311410 (130gr spitzer bevel base)
311413 (169gr spitzer gas-checked)
314299 (200gr round-nose gas check)

LEE (all sized to .310)
150gr FN gas-check
160gr Spitzer gas-check
185gr RN gas-check
200gr RN gas-check

I just realized that I have a ton of boolit molds! Well hopefully one or two of them will proved me an accurate load to punch paper with.

Bruce