I'm done...

[Burnt Fingers]

I've been trying to get cast boolits to shoot in my 300 Blackout AR Pistol for a few months now.

Nothing seems to work. I really wanted the MP 311410 boolit to work. If I can keep five rounds on a paper plate at 20 yards it's a miracle.

The NOE 311-158 FN is SLIGHTY better.

NOE 311-198 SP doesn't group either.

MP 311-235 is my last hope.

With the other four bullets, HP and solid on the 311410, I've tried a total of 72 loads. Several different powders.

The barrel is a 8.5" 1:7 twist. It will shoot j-word 125 gr bullets and 147 gr bullets into small holes.

Cast....forget about it.

It it too much to ask to have a semi-accurate cast load that functions in an AR-15?

[Winger Ed.]

1 in 7 seems like an awful fast of a twist for cast.
I ain't no expert, or even close to one, but I'd think you'd have a leading problem with it too.

[JMax]

I know with my Norwegian Krag in 6.5x55 (twist 1/7.5”) that most suggested loads were too hot until I throttled the velocity back to 1350ft/sec under the 140000 RPM limit. The question is what MV were you getting?

[rtyler8140]

1:7 is going to be the hurdle. Lower velocity will be more accurate, but may not cycle. My 300 AR is 1:10 and I'm seeing promising things from the Lee 150 & 170 with H110. I am running into similar issues with my 5.56 1:7. I found that if I push them too fast, I can't hit paper @ 50 yards. I have been able to get a 1.5" group @ 50 yards, but because im downloading the powder so much, it's pretty dirty.

[shortlegs]

The lee 155 for 7.62x39 works great in my ruger bolt gun and should work in your ar. I use h110 and lil gun, avg 2 in groups at 100 yds. 300 yrd gong is no problem. All my loads are super sonic. Alloy is WW and air cooled boolits

[PowPow]

OP: What's the hardness of your alloy? Lube(s)? Any leading? COL?

[charlie b]

Fast twist, short barrel. If you want this to cycle the action I suspect you are going to need a heavy bullet (230gn) probably around 1000fps.

If you use light bullets and try to drive fast enough to cycle the bolt, they will be spinning too fast for decent accuracy. Probably get leading as well.

If you insist on lighter bullets, I'd suggest powder coating as you might be able to get higher velocities without leading.

[Lloyd Smale]

ive got 2 ar15 300 pistols and one 16 inch rifle and all three of them shoot the rcbs 130 spitzer gas check real well. 2 inch or better groups at a 100 yards out of the rifle and the pistols with redots will do the same at 50. I cast them out of about 18bhn gas check them and pc coat them. That is with very little load development. Does it with 110 4227 and wc820. Couldn't get the 155 lee to run reliably out of my 16 so I never bothered any further with it.

[Burnt Fingers]

The alloy is half lino half pure.

All boolits have been either PC or Hi-Tek.

I haven't tried any gas checks as the molds are all plain base.

I've been looking for a slower twist barrel. The slowest I can find is a 1:8.5

There is no visible leading in the barrel...but the muzzle device has lead deposits and the tail of the bolt does too.

[gpidaho]

Burnt Fingers: A different barrel than yours but my 16" 1 in 8 300 Blackout AR really shoots well using the Noe 129gr.SP over 17gr. LilGun. These are gas checked and powder coated. Gp

[Green Frog]

When I built my 300 BO (Carbine length) I needed an adjustable gas valve on the barrel to get reliable functioning at subsonic speeds with light bullets. Have you considered changing your gas block and cranking it down almost all the way so you can back off on velocity? Lead deposits anywhere in the system are not desirable nor do they add to accuracy nor functionality.

I’m pretty much of a novice with the Blackout guns, but that’s how I would attack your problem (before investing in a new barrel with only slightly slower twist!)

Froggie

[Burnt Fingers]

I've been thinking about an adjustable gas block.

[lar45]

Lloyd, what kind of velocities are you pushing in the rifle and pistols?

[MrHarmless]

I also have a barrel at that twist rate. I highly recommend a heavy bullet, like 230 grain.

The Lee 309 230 5R works reasonably well for me. ~1.5 inches at 50 yards over a charge of H110.

[Larry Gibson]

Short barrel with a fast twist made for heavy bullets just subsonic.

With the 311410 PB PC'd cast bullet you, no doubt, are pushing them way too fast just to get reliable functioning and hence, no accuracy.

I suggest a heavier GC'd bullet in the 200 +/- gr weight range and keep them under 1300 fps. I'm not a fan of PC or HT coating but some seem to make it work. I prefer traditional lube.

[BK7saum]

What are your velocities? Since your molds are plain base, you probably wont be able to exceed 1500-1800 fps and still get accuracy. wrong mold for the problem. I'd bet a gas check mold would work much better. If you want some of the gas check MP311410 bullets holler at me. I dont have your alloy available though. I could cast some of straight wheelweights and water drop them if that would work. I like the 311410, but I shoot it hollowpointed and subsonic in a couple of bolt guns.

[Texas by God]

I got tired of spinning my wheels on my 1-7”.300 BO 16” carbine with cast. I simply wanted a flat nose boolit to go around 1800 FPS for hunting. I never got acceptable accuracy even sized at .311”. To make it worse, I built a 7.62x39 AR that shot the same boolit faster with great accuracy on the first try..... (1-10” twist). I’ll just use 110 and 125 j-words in the little Blackout and be happy from now on. I have zero interest in subsonic loads.

[Burnt Fingers]

I've got the MP 235 gr mold and boolits from it. I was going to load them up last week but my little buddy ended up at the vet Tuesday and I was taking care of him all week.

It's hard to give a bird meds...really hard.

He's doing a lot better now.

I'm going to load the heavies up and see if they work for me.

I have a carbine length 7.62x39 upper. I'll have to scrounge up some brass and give those lighter boolits a try in that. If it works I might get a pistol upper in that cartridge. I've got a spare lower or two laying around waiting for a project.

[dangitgriff]

I've been trying to get cast boolits to shoot in my 300 Blackout AR Pistol for a few months now.

Nothing seems to work. I really wanted the MP 311410 boolit to work. If I can keep five rounds on a paper plate at 20 yards it's a miracle.

The NOE 311-158 FN is SLIGHTY better.

NOE 311-198 SP doesn't group either.

MP 311-235 is my last hope.

With the other four bullets, HP and solid on the 311410, I've tried a total of 72 loads. Several different powders.

The barrel is a 8.5" 1:7 twist. It will shoot j-word 125 gr bullets and 147 gr bullets into small holes.

Cast....forget about it.

It it too much to ask to have a semi-accurate cast load that functions in an AR-15?

Try the 350 Legend instead. Easy conversion.

[Lloyd Smale]

load does between 1750 in my 7 inch gun to 2000 in the 16
Lloyd, what kind of velocities are you pushing in the rifle and pistols?

[Lloyd Smale]

When I built my 300 BO (Carbine length) I needed an adjustable gas valve on the barrel to get reliable functioning at subsonic speeds with light bullets. Have you considered changing your gas block and cranking it down almost all the way so you can back off on velocity? Lead deposits anywhere in the system are not desirable nor do they add to accuracy nor functionality.

I’m pretty much of a novice with the Blackout guns, but that’s how I would attack your problem (before investing in a new barrel with only slightly slower twist!)

Froggie

I think you've got it backwards. For those light loads and subsonic loads you want all the gas you can get so a standard wide open gas block (non adjustable) is perfect. Its when you start cranking up the pressures that an adjustable gas block can be a benefit. It lets you back off the gas and use only what you need.

[GooseGestapo]

Two pages and nobody mentions the most important consideration.
What is your sizing diameter?...

My .300BO shoots under 2moa with any cast bullet I’ve run through it. Running 1850-1,900fps.
I’m mostly using the Lee 155gr SemiPoint GC of w/w with 2%An/Sb solder added and lubed with SPG and Hornady GC’s. Also feeds Lee 150gr FNGC.
Also HF pc’d.

But I’m sizing .311”!
If you are sizing.308” or .309”, THERE is your problem.
My barrel is a No name 16” Mid length gas port, 1/8” twist. so will only cycle with supersonic ammo. I use Rl7, 4198, H110 and 1680 with equal success.

[Burnt Fingers]

I'm sizing to .310

I might have to give .311 a try. I think I have a NOE bushing in that size.

[Burnt Fingers]

Try the 350 Legend instead. Easy conversion.

I've been eyeing the 350 Legend pretty hard.

I haven't seen much about how it does in a shorter barrel though.

[cwlongshot]

Pryor to this year, I had the same story.
My Blk out shooting the loads they liked where better then I could have ever expected or hopped they might be. Im speaking UNDER 1/2 MOA. HONEST 1/3&1/4 MOA shooting!!

http://img.photobucket.com/albums/v465/CWLONGSHOT/35BD8E76-B7A3-4934-9509-148B9B1C25CD_zpsuqbmhir5.jpg (http://smg.photobucket.com/user/CWLONGSHOT/media/35BD8E76-B7A3-4934-9509-148B9B1C25CD_zpsuqbmhir5.jpg.html)

But cast was a frustration. I tried everything I had. I bought a couple molds BOUGHT bullets from couple suppliers. Took bullets from
Guys on
On line & friends who had success. Nope nothing shot to my satisfaction. Maybe my hopes are too high but I want sub 2" @ 100 and sub 1" @ 50. Sometimes Ill get there then a flyer will ruin things.

This year, I assembled another MSR in 300 and focused on sub loads. I bought a couple and loaded a BUNCH! I picked up Lyman Londs 311299, 311335, 311284 HP & Ideal 308389. Along with Lees 312-1552r and 160TL molds.

I sized 309,310 & 311 for all. I shot them GCd and not. I shot them subs and supers. I shot them conventional lube, TL and mostly PC.

A friend wanted some of my NOE 178RD bullets for his 30/30. I cast them with the deep HP pin for a 165g bullet. PC in Clear. I had them on hand and had 3032 in the hopper for the 30/30.... I loaded up 10 with 15.3g 3031 and that 165 HP seated @ crimp groove. This load cycled but refused to feed... BUT IT PUT BULLET AFTER BULLET INTO ONE HOLE @ 50 yards!!! Im talking a 50cal sized hole for all ten shots!!!!

Since then 4227 & RE7 have both done ALMOST as good. BUT ONLY WITH BULLETS THAT DONT FEED!! ?!?!?!??? GRRRR

I GOT THE LEE molds next. With high hopes I loaded both with 3031 & RE7. 16g was toos for the 155 shooting a loose 1" group in FOUR 300's the first day. The 160 was 1.5-2". Next week same rifles and ammo produced nearly same results but I moved to 100yards. 1.5 ish was bestnoutta the 155 @ 1300 fps. The 160 was 4" plus. (I really need to swear off TL bullets. They never shoot for me)

The 311299 (210g) shot pretty wall with all 4227 loads and OK with RE7.

The 311335 (220g) is still under the micro scope

The 311284 is a HP (208g )and needs to be tested. I just cast some last week and need time to season before testing.

Havent tested the 308389 yet. Its a very pointy 190g

Overall, I think that LEE 312-155 is my best and maybe can be refined more. I can hit steel out past 200 all day but thats a 12" plate... Not exactly precision.

My advice. Try more bullets!!

PM me and for postage Ill send ya what I have to try. Then you can buy your own mold if they pan out!

CW

[Dusty Bannister]

Is the fail to feed due to nose length preventing full chambering, or due to a fat nose not allowing the cartridge to enter the lands?

[Larry Gibson]

What was the velocity of the loads?

There is an RPM threshold of 120-140,000 RPM with cast bullets, especially the longer ones spun in fast twist. You're in that range at 1300 fps. Around 1350 - 1360 fps is going to be 140,000 +/- RPM given the 7" twist of your barrel. I suggest using a GC'd heavier bullet and drop the velocity to 1000 - 1300 fps.

[ACC]

I've been trying to get cast boolits to shoot in my 300 Blackout AR Pistol for a few months now.

Nothing seems to work. I really wanted the MP 311410 boolit to work. If I can keep five rounds on a paper plate at 20 yards it's a miracle.

The NOE 311-158 FN is SLIGHTY better.

NOE 311-198 SP doesn't group either.

MP 311-235 is my last hope.

With the other four bullets, HP and solid on the 311410, I've tried a total of 72 loads. Several different powders.

The barrel is a 8.5" 1:7 twist. It will shoot j-word 125 gr bullets and 147 gr bullets into small holes.

Cast....forget about it.

It it too much to ask to have a semi-accurate cast load that functions in an AR-15?

Back off the powder charge. Some times some guns will not shoot cast boolits except if they are slow. Like around 1200 FPS. These will not work the action though.

ACC

[Burnt Fingers]

What was the velocity of the loads?

There is an RPM threshold of 120-140,000 RPM with cast bullets, especially the longer ones spun in fast twist. You're in that range at 1300 fps. Around 1350 - 1360 fps is going to be 140,000 +/- RPM given the 7" twist of your barrel. I suggest using a GC'd heavier bullet and drop the velocity to 1000 - 1300 fps.

Hmm....

I was really hoping to shoot lighter weight cast boolits in this firearm. It sounds like the only way to accomplish that is going to be a custom barrel.

[Larry Gibson]

Hmm....

I was really hoping to shoot lighter weight cast boolits in this firearm. It sounds like the only way to accomplish that is going to be a custom barrel.

That does seem to be your conundrum.....

Your barrel was intended for heavy for caliber bullets at sub-sonic velocity. The fast twist is needed to stabilize those. If you want to shoot lighter weight cast bullets without any regard for them being sub-sonic then a barrel with a slower twist would be a good idea. A 14 or 16" twist will do for 150 gr bullets or less. The 30 Carbine's use a 18 or 20" twist. A 12" twist would be the fastest I would suggest and really may be best for bullet weights of 125 - 200 +/- gr weight for sub-sonic to 2000 fps +/- depending on bullet weight and length of barrel. That is with the 30 BO cartridge.

[Burnt Fingers]

That does seem to be your conundrum.....

Your barrel was intended for heavy for caliber bullets at sub-sonic velocity. The fast twist is needed to stabilize those. If you want to shoot lighter weight cast bullets without any regard for them being sub-sonic then a barrel with a slower twist would be a good idea. A 14 or 16" twist will do for 150 gr bullets or less. The 30 Carbine's use a 18 or 20" twist. A 12" twist would be the fastest I would suggest and really may be best for bullet weights of 125 - 200 +/- gr weight for sub-sonic to 2000 fps +/- depending on bullet weight and length of barrel. That is with the 30 BO cartridge.

I played around with the numbers last night and a 1:12" would be the fastest. Now to find a custom barrel that doesn't cost more than I have in this build.

[upnorthwis]

My 8:1 twist 5.56, With gas check = 2" or less @ 100 yds. Without gas check = Minute of berm or larger. There are people that say they get good results with PB, but I haven't seen it.

[lilMAC25]

I’m shooting the 247 gr NOE PB (subsonic) and not having any issues.

[Lloyd Smale]

I size to 309. Why because any bigger and they wont chamber in and of my 3 ar15s reliably and anything bigger then 310 wont even chamber in my ruger American. Even at 309 I about cant crimp because they then wont chamber so I just straighten out the flare in the crimp die. My 16 inch ar and American will do less the 2 moa at a 100 yards with 309s with the second load I tried (same load in both guns) So I guess I ask myself what 2moa wont take care of. It will easily give killing hits on man or deer sized targets at 300 yards. So as long as im not competitive shooting which I don't I have no need to find some magic 3/4 inch group load. Matter of fact I had a ball the other day. Just for grins I loaded some of the 130 rcbs spitzers with 4.5 grains of unique for a sub sonic load for my American with a can on it. They shocked me. I was expecting MAYBE 2 inch 50 yard groups and they ended up shooting 2 inch at a 100 yards! Sized? 309. A properly cut 30 cal barrel doesn't need bullets bigger then 309. They seem to do pretty good with jacketed at even 308.
Two pages and nobody mentions the most important consideration.
What is your sizing diameter?...

My .300BO shoots under 2moa with any cast bullet I’ve run through it. Running 1850-1,900fps.
I’m mostly using the Lee 155gr SemiPoint GC of w/w with 2%An/Sb solder added and lubed with SPG and Hornady GC’s. Also feeds Lee 150gr FNGC.
Also HF pc’d.

But I’m sizing .311”!
If you are sizing.308” or .309”, THERE is your problem.
My barrel is a No name 16” Mid length gas port, 1/8” twist. so will only cycle with supersonic ammo. I use Rl7, 4198, H110 and 1680 with equal success.

[Burnt Fingers]

After Saturday's range trip I've come to the conclusion that this barrel doesn't like cast bullets.

30 different heavy bullet loads and none of them would group.

[Conditor22]

http://www.x-caliber.net/custom-ar-barrel for $300

[tomme boy]

Who made the barrel?

Also the throat is the problem. They are throated long for the 200+gr bullets. They are not entering the bore straight.

[Conditor22]

I got a AR 300 BO Davidson Defense "Mercs" AR-15 Upper Receiver 16" .300 Blackout 4150 CMV 1-8T Barrel 15" M-Lok Handguard
@ 50 yards, initial load development, still need to fine-tune

rifle (had to seat the boolit 1/8" deeper to go into battery :( )
H110 8.1grn 7/8 group 247 FN GC
h110/296 8.7grn 1/2 group 1045fps L 312-155-2R

pistol

300 AAC BO 700X 4 1" NOE 247 FN GC

haven't tried the 155 grn

[Burnt Fingers]

Who made the barrel?

Also the throat is the problem. They are throated long for the 200+gr bullets. They are not entering the bore straight.

I'm not sure who made the barrel. If it's a throat problem then nothing I do can change that.

But here's the rub. I shot long boolits out of if this weekend. Same problem as lighter weight cast boolits. If the MP 235 isn't long enough then nothing is.

[Conditor22]

OK thinking outside the box, does the crown look OK?

[odfairfaxsub]

I shoot nothing but subs in mine. I do both gas checked and plain based subs. I have great success w my 1-7 twist. I use the 311-198 noe, the lee 309-230 and I use both versions of noe 311247 in lube grooves and slicksided.

[colonelhogan44]

I shoot nothing but subs in mine. I do both gas checked and plain based subs. I have great success w my 1-7 twist. I use the 311-198 noe, the lee 309-230 and I use both versions of noe 311247 in lube grooves and slicksided.

I'm about to start playing around with the Lee TL309-230-5R in a 1-7 twist. Any tips? I was thinking about starting by dipping the lube groove area in Johnson paste wax.

If they drop large enough, I'll probably load some up in 7.62x39 as well to feed my CZ527...it's a 1-9.5 so should be more forgiving.

[sutherpride59]

Man go watch some of “jonnys reloading bench” on YouTube. You will find that these short barrels like ours are just minute of man CQB tools. That fella bought the Ranier ultra match 9” barrel and was getting crap accuracy with the best copper jacketed he could fine. To add insult to injury all of his loads shot wonderful out of his $80 16” midway barrel. I’ve been loading for my 16” getting a sub load up for my suppressors but I guess it’s time I take my little guy out and cringe at the groups to see what I can do with him but you aren’t giving me much hope lol.

[Burnt Fingers]

OK thinking outside the box, does the crown look OK?

The crown is fine.

It shoots plated and jacketed bullets just fine.

[Conditor22]

I may just be a blind old man but I didn't see where you slugged/did a chamber cast or pound cast of your barrel.

see what the largest boolit that will fit - go into battery. -- running out of options :(

[sutherpride59]

To be honest I’ve had the best success in mine shooting subs with unsized boolits. Try using a .312 sized or just don’t size at all and see what you get. I suspect for subs it was more of a need to build up pressure with my soft alloy though.

[Tonto]

Great thread, more outside the box and there is no mention of the sights you are using.....Once in awhile trouble can be traced back to a loose mount or a flawed dot or crosshair adjustment.

[Finster101]

Man go watch some of “jonnys reloading bench” on YouTube. You will find that these short barrels like ours are just minute of man CQB tools. That fella bought the Ranier ultra match 9” barrel and was getting crap accuracy with the best copper jacketed he could fine. To add insult to injury all of his loads shot wonderful out of his $80 16” midway barrel. I’ve been loading for my 16” getting a sub load up for my suppressors but I guess it’s time I take my little guy out and cringe at the groups to see what I can do with him but you aren’t giving me much hope lol.


There is no reason you can not get good accuracy out of a short barrel.

[Burnt Fingers]

Great thread, more outside the box and there is no mention of the sights you are using.....Once in awhile trouble can be traced back to a loose mount or a flawed dot or crosshair adjustment.

If that were the case then the plated bullets would have the same problem. They don't.

I'm using a scope on the beast right now. Before that I had a Sig Red Dot.

I have not slugged the barrel. I went right to .310 bullets. A outsized bore on a 30 caliber barrel would be strange indeed.

[dverna]

After Saturday's range trip I've come to the conclusion that this barrel doesn't like cast bullets.

30 different heavy bullet loads and none of them would group.

I doubt changing the barrel will get you where you want to be. I did a lot of research and even invested in a Mi-Hec "NATO" mold for the AR in 5.56. It seemed that nearly everyone getting any success (defined by 2 MOA and cycling the action) had to weight sort and use gas checked bullets. My casting abilities are sub-par (+/- about 1.25 gr on pistol bullets) so getting consistent itsy-bitsy bullets seemed unlikely...but others can do it. BTW, easy to check how good you are by test weighing 50 of whatever bullets you currently cast.

I decided buying bulk Hornady 55 gr SP bullets made more sense. They go on sale for $420 delivered for 6000. Gas checks for 6000 bullets will cost $120, hard ball alloy added $100 and I was at 50% of the cost of decent SP bullet that will be twice as accurate. Then add in the cost of molds, wasted components to find a marginal load, and the time.

I estimated:
A casting rate of 600/hr.
Sorting rate of 1000/hr
GC/Lube rate of 300/hr.
Cull rate of 50% if sorting.

If you can use bullets without sorting. Time to produce 6000 bullets is 30 hours...for a saving of $200 (under $7/hr)
If you must sort bullets. Time to produce 600 bullets is 46 hours...saving $200...works out to less than $4.50/hr

Before investing in another barrel and more molds/development ...look at the economics, the time you have, as well as your casting ability.

With a usage of about 2000 5.56 a year, buying MOA jacketed SP bullets made the most sense in my situation. I need to "save" at least $10/hr to justify casting or reloading. I am retired and have plenty of time but I have more fun doing other things.

[popper]

the muzzle device has lead deposits and the tail of the bolt does too.
Reduce the load. 8" is kinda short, dwell time for fast is short so not much gas until you get to hotter loads. My 10" 1:8 does fine with 31-142C, but pistol gas at HV really gets lead on the bolt tail and rings get stuck. Lead on the muzzle is indicative of some gas cutting. Try 9 gr A2400 under the 145-150ish and see how you like it. Will cycle action and ~ 1600 fps. 9 gr cfe pistol cycles my action too.

[Burnt Fingers]

I doubt changing the barrel will get you where you want to be. I did a lot of research and even invested in a Mi-Hec "NATO" mold for the AR in 5.56. It seemed that nearly everyone getting any success (defined by 2 MOA and cycling the action) had to weight sort and use gas checked bullets. My casting abilities are sub-par (+/- about 1.25 gr on pistol bullets) so getting consistent itsy-bitsy bullets seemed unlikely...but others can do it. BTW, easy to check how good you are by test weighing 50 of whatever bullets you currently cast.

I decided buying bulk Hornady 55 gr SP bullets made more sense. They go on sale for $420 delivered for 6000. Gas checks for 6000 bullets will cost $120, hard ball alloy added $100 and I was at 50% of the cost of decent SP bullet that will be twice as accurate. Then add in the cost of molds, wasted components to find a marginal load, and the time.

I estimated:
A casting rate of 600/hr.
Sorting rate of 1000/hr
GC/Lube rate of 300/hr.
Cull rate of 50% if sorting.

If you can use bullets without sorting. Time to produce 6000 bullets is 30 hours...for a saving of $200 (under $7/hr)
If you must sort bullets. Time to produce 600 bullets is 46 hours...saving $200...works out to less than $4.50/hr

Before investing in another barrel and more molds/development ...look at the economics, the time you have, as well as your casting ability.

With a usage of about 2000 5.56 a year, buying MOA jacketed SP bullets made the most sense in my situation. I need to "save" at least $10/hr to justify casting or reloading. I am retired and have plenty of time but I have more fun doing other things.

I'm not shooting 223. I'm shooting 300 Blackout. There's a LOT of difference between the two. If you can find me 300 Blackout bullets for $420/6000 I'm all ears.

[Burnt Fingers]

Reduce the load. 8" is kinda short, dwell time for fast is short so not much gas until you get to hotter loads. My 10" 1:8 does fine with 31-142C, but pistol gas at HV really gets lead on the bolt tail and rings get stuck. Lead on the muzzle is indicative of some gas cutting. Try 9 gr A2400 under the 145-150ish and see how you like it. Will cycle action and ~ 1600 fps. 9 gr cfe pistol cycles my action too.

I did try reduced loads that would not cycle the action. It was still spraying bullets all over the target.

[sutherpride59]

If you want I have a PSA 9” barrel I can loan you for testing if you want. I plan on using it to build my brother a pistol with a brace when he turns 21 in October.

[Conditor22]

What powder/ loads have you tried with what boolits?
Short barrel = Faster powder

"I'm sizing to .310 I might have to give .311 a try. I think I have a NOE bushing in that size."

You could size to 310 then PC them larger.

[Landshark9025]

Try the Lee 312-155 2R with about a 93/5/2 alloy, gas checked, sized to .310, seated to the crimp groove, over 14.8g of Lil Gun with Remington 7 1/2 primers.

I have a 10” AR Pistol with 1:7 twist that will do 1.25 MOA at 100 with that and function flawlessly.

Note: That is a starting load and got me about 1822 FPS. As the charge weights went up, accuracy got worse. I’d play at the bottom end if I were you. I like this as it makes for cheap loads.

[Hairy Dawg]

I shoot a BCM 9" 1/7 sbr. I load 142 grain NOE plain base, powder coated bullet. My first loads were loaded with Lil Gun, and I struggled to get subsonic speeds while maintaining cycling, unsupressed, but with tinkering, was able to get there. 1680 was much easier to maintain cycling while keeping subsonic speeds unsupressed. I really haven't tried stretching it out to 100 yards, but at 50 yards, I'm more than happy.

[Burnt Fingers]

What powder/ loads have you tried with what boolits?
Short barrel = Faster powder

"I'm sizing to .310 I might have to give .311 a try. I think I have a NOE bushing in that size."

You could size to 310 then PC them larger.

With the MP 311410 I've tried H110, MP-300, Heavy Pistol, CFE Black, and 1680
With the NOE 158 the same powders plus Reloader 7
With the NOE 198 1680, CFE Black, RL7, IMR 4227
With the MP 235 the same as the NOE 198.

[Burnt Fingers]

What powder/ loads have you tried with what boolits?
Short barrel = Faster powder

"I'm sizing to .310 I might have to give .311 a try. I think I have a NOE bushing in that size."

You could size to 310 then PC them larger.

I coat then size.

[Burnt Fingers]

If you want I have a PSA 9” barrel I can loan you for testing if you want. I plan on using it to build my brother a pistol with a brace when he turns 21 in October.

Thanks for the offer.

Right now I'm in the process of converting this from a side charger to a top charger. Since I really wanted this as a supersonic lightweight launcher I'm pretty sure I'm going to order a custom 10.5" barrel in a slower twist with a carbine length gas system.

McGowen will do a custom barrel for $245.

[Conditor22]

Are you getting an adjustable gas block?

[popper]

My carbine 1:10 is McGowen, works great, but check Xcaliber(?) to see what they have. My pistol barrel is Kak cheapie and works fine also 1:8.

[Burnt Fingers]

I'm seriously thinking about an adjustable gas block for the build.

[Conditor22]

My AR pistol is 8" barrel -w- 1:8 twist [drew a line down both sides of a cleaning rod with a brush], taped a thread across the muzzle, marked where the rod started turning and marked when the rod went 1/2 way around -- X 2 = 8 :)]

air shot a 1" group with NOE 247 FN without a GC on it over 4 grns 700X -- no it didn't cycle

You said 1 load shot L, C, R, L, R. makes me wonder if there is a problem with the crown.
I'm just surmising now but the jacketed bullet doesn't fill the bore so wouldn't be affected /as adversely affected by a bad crown.

Did you ever slug the barrel? IF it's a new barrel maybe you need to send it back and exchange it for another one.