300 AAC Blackout

[MGySgt]

I am looking for any success stories with cast and 300 AAC Blackout. I am not sure what boolits are suitable to use in the 300.

I have the RCBS 165 gr GC Sil that I am going to try when my dies come in. (Dies ordered but shipping department was shut down for Christmas/New Years Holiday).

Any input will be appreciated. I will have 3 of these things to feed (Son and Grand son besides mine).

[Jailer]

That boolit should feed well for you. I have a MP 180 Sil and it feeds fine in mine. The best all around cast boolit seems to be the Lee 312-155-2R. Haven't heard of anyone yet that has any feeding or accuracy issues with this boolit. If you want to shoot subsonics you'll have to do some more research as I haven't shot many subs.

H110, Power Pro 300 MP, AA1680, 4227, 4759, AA5744 or RE7 will be your powder choices for a heavier supersonic load. 4198 is probably just a tad slow for a 165gr boolit for supers. Lilgun is another good powder for this round but too fast for the 165gr to provide reliable cycling.

[fcvan]

There is a great deal of discussion regarding the 300 bulk over on the 'CB loads Military Rifles' and 'CB loads favorite cartridges' threads. I've assembled the dies/molds/sizer and have an upper on order. There is also great threads on 300Blk talk, another web discussion board.

This weekend, I was able to score a built 300 blk at a gun show so I can start assembling loads for testing. The Mrs really liked her AR in 5.56 (just finished) and when I told her I was building a 300 blk she chimed in with 'I want one.' This first one is hers and I will use it to work up loads in preparation for my upper coming in.

I will be starting with the Lee 312-155 2R, IMR 4227, gas checks made with a CheckMaker die, powder coated with a Harbor Freight ES powder coat gun, and sized with a Lee push through die. I've made up 400 pieces of 300 blk using LC 5.56 brass.

As this is a SAAMI cartridge there is a wealth of load data from Sierra, Hodgdon, etc., from various powder manufacturers. As far as cast goes, lots of folks are working up subsonic loads for use with 200+ grain boolits that cycle AR platform rifles with or without a suppressor. As stated earlier, I'm going to start with the 312-155 as there is a lot of data with that and 4227 powder. I'm already using 4227 in my 5.56/.223 loads for my AR and Mini 14 rifles. This will be a fun project, especially now that I can actually start load development and do some testing.

[Jupiter7]

Another vote for the 312-155. I've shot it 90-1 of all other boolits combined. Best accuracy has been with noe 311-165 sized .310 and tumbled in LLA over 13.5grs of lil gun(1690fps) sub-moa from a 10" AR pistol. Doesn't feed well enough for everyday use though.

[MGySgt]

Thank you for your responses. Gives me a starting point.

Finally got a chance to shoot this thing. - Anyone that wants to shoot a rifle and may be recoil sensitive can shoot these. I have an in-expensive tactical scope that I put on it. Not really happy with the accuracy - probably the scope is too busy. I will swap it off before I start load development.

I have a number of the RCBS 165GC cast - with a number of them sized and lubed also. That is where I am going to start only because I have them.

I have the Lee 312-155 also, thought I had some cast up but can't find them. Time to fire up the pot and get some cast. I just need to find the correct top punch for it. I have it written down someplace - just need to find it again.

I was hoping that some one would come through with a load with 2400. I have shot it in the 5.56 AR platform, but it would not cycle, that is it would eject but not pickup the next round.

[Jailer]

I have the Lee 312-155 also, thought I had some cast up but can't find them. Time to fire up the pot and get some cast. I just need to find the correct top punch for it. I have it written down someplace - just need to find it again.

467

http://www.castpics.net/subsite/TopPunches/Lee.html



I was hoping that some one would come through with a load with 2400. I have shot it in the 5.56 AR platform, but it would not cycle, that is it would eject but not pickup the next round.

2400 is a great powder and does well in a bolt gun but as you discovered it is too fast to provide enough gas volume for reliable functioning.

[MGySgt]

Thank you Jailer.

[Boolseye]

My 300 BLK is accurate with a wide variety of boolits. My favorite is the Lee 312-160, which is a TL mold. I have two so I can cast them fast. Has to be loaded to about 1.985 (if memory serves) or it won't chamber. It also likes the Lee 309-170 a lot. Both these rounds cycle the action of my carbine with fairly low loads (16 grains #7). The heavies are a little less fun for me 'cause they're harder to get to cycle. I have the Lee 309-230-5R. Shoots good, but haven't cycled it yet. You can put a gas check on the 230 if you like. It squeezes right on to the boat tail like it was made for it. Fun gun.

[MGySgt]

Just got my dies yesterday - and will start working on a load for the RCBS 165Gr GC Sil. Suppose to be warmer were in the next few days so I can go to the casting shed to cast up some of the Lee's.

Report will come after the initial tests

[Green Frog]

If somebody has a proven 300 BO load using 4759 for a supersonic with any bullet weight I would love to hear it. In these tough powder days I have about 10# of it left from previous endeavors. Also, does anyone have a good supersonic load using Accurate #9? (I know it's a stretch, but I've got a bunch of that, and I know it worked in some other relatively small rifle cases.

TIA ~ Froggie

PS Is anyone using either the Ideal 311359 GC bullet designed for the M1 Carbine or the 3118 PB designed for the 32-20 to make a round for the 300 BO? Can you get enough pressure behind one of them to reliably operate the AR mechanicals?

[Ford SD]

Im interested in any RCBS 165 sil data for the 300 blk
I have shot the 180g sil and 1680 and had 95% full function with start up loads on a brand new rifle (less than 50 rounds total through it)
have some 165 sil loaded up for testing but it is so cold out, I dont want to go to the range to have frozen lube problems
also have problem with hands so after shoveling snow can't feel trigger finger

not sure on accuracy as was using a red dot (less than 2-1/2 5 shot groups at 50) with red dot at max -->now changed

First loads were on the light side/ loaded a bit long and gave me a dirty action----> fail to feed (hang up on ramp)

1/8 wilson 16" barrel

[Green Frog]

How about the Lyman 311410 bullet (PB 130 gr) designed for the M1 Carbine? I just found that design on the I-net and it looks promising, based on what I have already read... :coffee com

Froggie

[Dr.Phil]

Also, does anyone have a good supersonic load using Accurate #9? (I know it's a stretch, but I've got a bunch of that, and I know it worked in some other relatively small rifle cases.

TIA ~ Froggie

Accurate #9 works great for 300 BLK supersonic loads.
15.5 grains under a 110 grain bullet is a safe place to start.

[Green Frog]

Accurate #9 works great for 300 BLK supersonic loads.
15.5 grains under a 110 grain bullet is a safe place to start.

Cool, Dr Phil! Many thanks. Sounds like just what I need. That 12+ lb of it I bought will go very well and last a long time. Now to get my Mihec mould in that weight to appear... :?

Froggie

[Dr.Phil]

Cool, Dr Phil! Many thanks. Sounds like just what I need. That 12+ lb of it I bought will go very well and last a long time. Now to get my Mihec mould in that weight to appear... :?

Froggie
No problem...
FYI, N110 is by far the best powder for supersonic 300 BLK loads.
Super clean, very accurate and close to 100% case fill.
The AA#9 works well, but the case fill is only about 75% which can lead to consistency issues.
It is possible to over charge the 300 BLK case with AA#9 to the point where I would be concerned about case failure.
Have fun, but be careful...

[MGySgt]

The RCBS 165 gr GC Sil will not work in my 300 AAC Blackout - will not chamber all the way. The front of the nose is too large and jams into the rifling.

Had a rough time getting the round out of the chamber.

My upper is a S&W M&P 300 Wisper/AAC Blackout in 1-7.5 twist.

Need to cast some of the Lee's 312 155. Now that the weather is a little warmer I can go to the casting shed. I really need to make a chamber casting of mine and my son's to see just what we have here.

[MGySgt]

N110? Is that the same as H110 and Win 296?

[felix]

NO! ... felix

N110 is associated with 2400, WW820 (faster lots), AA9. ... felix

[mtnman31]

N110? Is that the same as H110 and Win 296?

No, not the same. N110 is faster burning than H110/W296.

[MGySgt]

That is what I thought - Just wanted to be sure.

Thank you Felix and Mtnman31.

Don't understand Dr. Phil's statement that N110 is about perfect for the 300 where as 2400 won't cycle it..
Confusing as usual!

[fastfire]

Im interested in any RCBS 165 sil data for the 300 blk
I have shot the 180g sil and 1680 and had 95% full function with start up loads on a brand new rifle (less than 50 rounds total through it)
have some 165 sil loaded up for testing but it is so cold out, I dont want to go to the range to have frozen lube problems
also have problem with hands so after shoveling snow can't feel trigger finger

not sure on accuracy as was using a red dot (less than 2-1/2 5 shot groups at 50) with red dot at max -->now changed

First loads were on the light side/ loaded a bit long and gave me a dirty action----> fail to feed (hang up on ramp)

1/8 wilson 16" barrel

I shot the 180g sil yesterday 13gr Lilgun 1632fps sd 9 powder coated col 2.064.100% Cycled

Grouped ok but need to work up a betterload.
16" Noveske

[Dr.Phil]

That is what I thought - Just wanted to be sure.

Thank you Felix and Mtnman31.

Don't understand Dr. Phil's statement that N110 is about perfect for the 300 where as 2400 won't cycle it..
Confusing as usual!
N110 as in Vihtavuori N110
http://www.lapua.com/en/products/reloading/vihtavuori-powders

It cycles a 300 BLK AR just fine, burns extraordinarily clean, has 100 % case fill, and yields outstanding accuracy.
My accuracy load is 18.0 grains of N110 under a 125 Grain SMK and federal 205M primer.
http://www.l8ntactical.com/storage/forum_images/P1010272_WEB.jpg
(10" Noveske Barrel, Pistol Gas, 1:8 Twist, and TBAC 30P-1 Suppressor)

[geraldsd]

What scope do you have on your BO, Dr. Phil? I have a 312 155 Lee mold. I intend to size it to.309, lube it with Rooster Red, and of course GC it. I will use either WC 820 or 4227. I want to load for about 1800 fps. I have read about 16.5 grs for H110 on this forum and that goes well with what I have learned with jacketed bullets. The only thing that I worry about is sizing down the 312 bullet to .309. I guess everyone is doing it, but I always heard that excessive sizing was harmful to accuracy. These are just my thoughts. What are others experiences?

[Dr.Phil]

What scope do you have on your BO, Dr. Phil? I have a 312 155 Lee mold. I intend to size it to.309, lube it with Rooster Red, and of course GC it. I will use either WC 820 or 4227. I want to load for about 1800 fps. I have read about 16.5 grs for H110 on this forum and that goes well with what I have learned with jacketed bullets. The only thing that I worry about is sizing down the 312 bullet to .309. I guess everyone is doing it, but I always heard that excessive sizing was harmful to accuracy. These are just my thoughts. What are others experiences?
I run a Leupold Mark 4 3.5-10x40mm LR/T M3 Front Focal Riflescope with a TMR Reticle on my ARs.
I'm a competitive long range precision rifle shooter and tend to use more magnification than most for a given application.
Leupold has a Federal / Mil discount program that keeps me brand loyal. (I like good glass, but I'm cheap...)
3.5 power is low enough for me to have enough field of view for close in work and I either switch the scope out for my Tijicon Tripower or mount a Delta Point on top of the scope if I need a zero power aiming solution.

As for cast supersonic projectiles, I have not been brave enough to get into that yet.
My 300 BLK upper is setup for a full time suppressor and I did not want to risk a GC coming loose inside of it.
With powder coating becoming all the rage, I will likely try that out with a 175 grain cast boolit that is optimized for feeding in an AR.
That will give me an inexpensive supersonic plinking boolit that I can also use for 3 Gun and will make Major PF.

[MGySgt]

I have been fighting with my cast to chamber in my 300 BO. I thought my problem was the nose was too fat and it was jamming on the top of the Lands.

Cast sized to .311, brass formed from LC 5.56 MilSpec brass.

I just took some measurements on loaded rounds on the Neck.

Factory 300 AAC Blackout RP Brass - .331.
Cast .311 in a commercial case - .332/3.
Cast .311 in MilSpec 5.56 formed brass - .335.

.335 is just a little bit too large to chamber in the neck area. I am going to size some of my cast to .309 and start over.

More to follow I am sure.

[Dr.Phil]

With a Noveske Barrel, I size my 247 Grain NOE FN boolits to .309 and they are good to go.
The mould puts them out at .311 and I use a Lee sizing die to get them to .309

[MGySgt]

I have an old .308 die here that I am going to hone out to .309 and go from there.

[Boolseye]

.335 is just a little bit too large to chamber in the neck area.
That has been my experience. Notice that it is the thickness of the brass in some cases that causes this problem, exacerbated by oversized slugs.

[MGySgt]

Notice that it is the thickness of the brass in some cases that causes this problem, exacerbated by oversized slugs.

It is the brass - If I use the formed brass from 5.56 the .311 bullet won't chamber, but if I use the RP factory brass they will chamber.

Just have to tailor my cast to the brass - Which by the way is not uncommon when we deal with reformed brass that has been shortened.

I could just 'uniform' the necks and bring them down to SAAMI Standard- but when we are dealing with 2 to 3K of brass - I think it makes more sense to tailor the boolit size to the brass and spend more time shooting.

Now the above statement could change due to leading of the rifle, or problems developing in the gas system. Time will tell.

Time and weather permitting I have 3 different loads to test today with the RCBS 165-SIL and Accurate 1680. Initial test yesterday seemed promising.

[GabbyM]

http://castboolits.gunloads.com/attachment.php?attachmentid=50091&d=1232425178

Any of you ever try the 150 grain Saeco #316 flat nose in a 300 Blackout? Second from left in photo.
I like it for high production 30-30. Bullet is just the right length it drops into my Star size die leaving the base sticking up just enough to place a gas check. Flat nose doesn't dent the gas check on bullet below it. Plus Saeco makes it in a four cavity. Longer or pointy bullets I use my Lyman size machine at about one third the production rate. If it would feed it would be a good super sonic shooter.

[MGySgt]

First real test:

300 AAC BO, LC 2012 MilSpec formed cases
RCBS 165gr GC Sil bullet, actual weight = 175gr ready to load Lubed with Lyman Super Moly (Why? Because those are the ones I picked, I have some lubed with LBT Blue too!)
Accurate 1680.
COL 2.200 (Yes I know it is short, but if I go longer the first driving band will jam into the rifling.)

50 yards benched

17.5 gr - 1.2 C to C with a 2 inch flyer at 12:00.
18.0 gr - 1.2 C to C lateral dispersion.
18.5 gr - 1.5 C to C with a 3 in flyer at 12:00

I need to load some more of the 17.5 and 18.0 and re-zero the scope and move to 100 yards. Both show promise to stay under 3 inch at 100 yards which is what I am looking for. Velocity doesn't matter as long as the rifle functions - but I will chronograph the loads to see what they are doing.

[MGySgt]

http://castboolits.gunloads.com/attachment.php?attachmentid=50091&d=1232425178

Any of you ever try the 150 grain Saeco #316 flat nose in a 300 Blackout?.

I think the base is too long and would drop down below the shoulder and expose the lube to the powder. I believe any cast boolit that works in a 308 Win probably will work in the 300 BO.

[GabbyM]

From the crimp grove to base it's .415". That places top of gas check just below a 308 case neck but grease is still in neck. However there is no front band above the crimp grove. It's .300" bore diameter. Thus in a 308 I'd set it out a bit and use no crimp in a bolt gun. In my 30-30 I seat them to the grove and use a light crimp. Total length of bullet is .880" with a .190" meplate.

[MGySgt]

I am getting ready to walk out the door for a weekend trip - how about we get together early next week and I will try to talk you out of about 50 of them so I can try them.

Might be a good choice for blaster ammo as it might be more accurate than my RCBS 165 SIL and even if it only matches it - the RCBS is a 2 banger - The Saeco is a 4 Cavity?

[Boolseye]

The only thing that I worry about is sizing down the 312 bullet to .309. I guess everyone is doing it, but I always heard that excessive sizing was harmful to accuracy. These are just my thoughts. What are others experiences?
MGySgt: There will be no problem sizing that Lee 155 down to .309", and the GC will be on tighter, too. I shoot that boolit's sister, the 312-160, sized to .309" and get respectable accuracy. That said, it will probably shoot better at .311"-the problem, of course, is the chambering issues that can cause.

[yondering]

That is what I thought - Just wanted to be sure.

Thank you Felix and Mtnman31.

Don't understand Dr. Phil's statement that N110 is about perfect for the 300 where as 2400 won't cycle it..
Confusing as usual!

2400 cycles the 300 Blackout AR15 just fine with supersonic loads, unless the gas system or buffer weight is wrong. 2400 is not a great choice though; velocity is low and it gives a lot (I mean a LOT!) of flash. There are several better choices out there.

Personally I think Lil'Gun is the ideal 300 Blk supersonic load powder. Velocity is similar to H110, but with a lot less flash and blast. Anything faster than H110 is really too fast for maximum velocity with 110-125gr bullets.

[yondering]

I also use the Lee 155gr bullet. It shoots pretty well (I powder coat mine) and can be pushed to about the same velocity as a 125gr jacketed bullet.

The problem with the Lee 155, and most other cast bullets when used in AR15's, is the ogive diameter at the magazine rib. If they are seated to an optimum depth for the chamber, they feed poorly, and stack up in the magazine wrong. My P-Mags won't feed right with more than 15 of these loaded at once because of this issue. A long tapered nose is better for feeding in this round, but so far the only cast bullet I've seen with that kind of profile is the Lee 230gr, which of course is for subsonic use.

[GabbyM]

I am getting ready to walk out the door for a weekend trip - how about we get together early next week and I will try to talk you out of about 50 of them so I can try them.

Might be a good choice for blaster ammo as it might be more accurate than my RCBS 165 SIL and even if it only matches it - the RCBS is a 2 banger - The Saeco is a 4 Cavity?

Pm me your addy:

Flat nose should be better smack down for any hunting application. Have a big box of them here in BHN #9 alloy. I shoot those over 26 grains of Rx7 in the 30-30 Win 94 AE with 12 twist barrel. Never clocked them but they still hit in the front sight dot at 100 yards so they are over 2,000 fps. I’ll need to cast you up some hard ones for a fast twist barrel.

My mold is set up in a Magma one arm bandit casting machine. Then yes Saeco sells the four cavity that will run many per hour. Big production point is it will run through a Star size machine. Most rifle bullets actually do not very well.

If this flat nose will not run in a 300 Black out I don’t know what FN would. Have been looking for a few years waiting to see this bullet show up in the 300 BO threads. Well dugh I guess we’ll see. I’m no big 300 blackout fan but my son in law is all excited about getting one. Since he reads magazines. So I need a boolit. Lol

We’ll need to try the MP 180 HP also. And the lyman 311672.
Just for giggles. If that’s to much work on your schedule just say so.
Not looking to dump work on you.

[Boolseye]

If this flat nose will not run in a 300 Black out I don’t know what FN would.
Lee 309-170 feeds great for me.

[Jbiker]

what COAL were you ending with ?

[Jbiker]

what COAL were you ending with ? sounds like your too long ,if your hitting the rifling. max for the coal 2.260. seems like you should be around 2.200/2.240..for feeding out of a standard mag .

[karlrudin]

N110 The fastest burning rifle powder from Vihtavuori. Similar to Hodgdon H110 and Winchester 296. N110 can be used in small rifle cases like .22 Hornet and .30 Carbine but also in magnum pistol and revolver cartridges like .357 S&W Magnum, .41 Magnum, .44 Magnum, .454 Casull and .500 S&W.

[felix]

N110 is NOT similar to H110/WW296, but more like 2400 in application. N105 is Vihtavuori's fastest rifle powder in this country, and that is like BlueDot. ... felix

[felix]

Remember, what cycles the gun and doesn't depends on the shape of the pressure curve produced by the cartridge as loaded. ... felix

[Boolseye]

what COAL were you ending with ?

For the Lee c309-170 F, my OAL is 1.927". With 15.5 grains of RL7, it cycles the action fine. I would estimate velocity between 1500-1600 fps from 16" carbine.

[MakeMineA10mm]

Remember, what cycles the gun and doesn't depends on the shape of the pressure curve produced by the cartridge as loaded. ... felix

To add to felix' point, remember with the AR's DI gas system, the gas volume (amount of gas created compared to the space it needs to fill) and dwell time (dictated by the distance from the gas port to the muzzle) effect functioning of the action too.

[fcvan]

Great, now I have to remember all the stuff I slept through when the teacher was giving a lecture on fluid dynamics :)

I actually considered the dwell time of the pressure wave when comparing the volume of the .223 barrel and the .308 barrel when factoring in a 14 drain load of 4227. The 5.56/.223 loads I'm using have reportedly been cycling the 300 blk with a 155 gr boolit. Granted, the velocity is lower but the pressure wave seems adequate to cycle the action. The top end charge of 4227 for a 155 is higher, but cycling has reportedly begun at closer to 12.9 grains. I don't know personally, my upper parts are still on order.

I don't know the size of the gas port on the 300 I'm getting, or the port size of the 5.56 I've built. I know some folks have enlarged their ports, and added adjustable porting, in order to run subsonic loads. I don't intend to run subsonic but I'm sure I will play with it over time. My main focus is to launch the Lee C312-155 2R with a decent mid range plinker, work up some performance rounds just because, but mostly run mid range to save wear and tear on the gun and the brass. I'm looking forward to testing things out, and applying the principles learned here and from classes I didn't actually sleep through.

[saz]

Pm me your addy:

Flat nose should be better smack down for any hunting application. Have a big box of them here in BHN #9 alloy. I shoot those over 26 grains of Rx7 in the 30-30 Win 94 AE with 12 twist barrel. Never clocked them but they still hit in the front sight dot at 100 yards so they are over 2,000 fps. I’ll need to cast you up some hard ones for a fast twist barrel.

My mold is set up in a Magma one arm bandit casting machine. Then yes Saeco sells the four cavity that will run many per hour. Big production point is it will run through a Star size machine. Most rifle bullets actually do not very well.

If this flat nose will not run in a 300 Black out I don’t know what FN would. Have been looking for a few years waiting to see this bullet show up in the 300 BO threads. Well dugh I guess we’ll see. I’m no big 300 blackout fan but my son in law is all excited about getting one. Since he reads magazines. So I need a boolit. Lol

We’ll need to try the MP 180 HP also. And the lyman 311672.
Just for giggles. If that’s to much work on your schedule just say so.
Not looking to dump work on you.


Gabby & MGySgt,
I am very curious as to weather the Saeco boolit will work in the 300BO. I just built one and I am looking for a good hunting boolit. I know everyone has great luck with the Lee 155, but I want either a larger meplat or a HP. The problem that seems to happen with the HP is it gets crushed while cycling. I am a fan of larger meplats for hunting anyways. I am still waiting for dies and case length trimmer to make brass for now. PLEASE keep us updated with your results! Good Luck!

[karlrudin]

according to Vihtavuori, there is no N105 and N110 IS there fastest rifle powder, http://www.lapua.com/upload/downloads/brochures/2011/vihtavuorireloadingpowdersleaflet2011eur.pdf

[MGySgt]

Pm me your addy:

We’ll need to try the MP 180 HP also. And the lyman 311672.
Just for giggles. If that’s to much work on your schedule just say so.
Not looking to dump work on you.

Snail Mail address sent.

I enjoy working a load more than just shooting so send them on - just don't expect results over night!

[MGySgt]

what COAL were you ending with ?

I assume you were talking to Boolseye.

[MGySgt]

what COAL were you ending with ? sounds like your too long ,if your hitting the rifling. max for the coal 2.260. seems like you should be around 2.200/2.240..for feeding out of a standard mag .

2.200 COL is what I reported in the first real test.

What is hitting the rifling is the first driving band. Boolit has plenty of space in the mag.

[MGySgt]

PLEASE keep us updated with your results! Good Luck!

I will report all my findings in this thread.

[MakeMineA10mm]

according to Vihtavuori, there is no N105 and N110 IS there fastest rifle powder, http://www.lapua.com/upload/downloads/brochures/2011/vihtavuorireloadingpowdersleaflet2011eur.pdf

I can post a pic of my bottle of N105, if you'd like. IIRC, they listed N105 in their pistol powder line (the N300s), because it was so quick-burning, it's applications mostly all fall in magnum pistol applications. Still, it is an N100-series powder, and so, technically, is part of their rifle product line.

[DanWalker]

Saz drug me into the 300 madness. Got a barrel, bolt, reloading dies and brass, waiting for me to get home. I will be watching this thread with great interest also

[Green Frog]

I've got everything to build my 300 AAC Blackout except the adjustable gas block and flash hider. I may change my mind and swap out my hand guard and may do an initial build using a standard block from a previous 5.56 build. I guess I can even omit my flash hider and run with bare threads for a while. Ultimately I want to use a dedicated BCG and CH, but for testing will swap them in from my nearly new 5.56 upper.

Anyhooooo, I am eagerly watching what you folks have to say about lead bullet loads for this new-to-me caliber so I don't end up chasing rabbits when I can benefit from your shared experiences. Thanks in advance! :coffeecom

Froggie

[felix]

NO, no! Get the variable block, and make sure you can get max possible pressure out of it AND the barrel. This is assuming you have the carbine length gas system. Pistol length system would be ideal so all kinds of real pistol powders can be used to make all kinds of loads from mild to wild. Then no variable gas block would be needed. ... felix

[Green Frog]

Thanks, Felix. Gun show this weekend! ;)

Froggie

[felix]

Do this thing right, Froggie, and you won't need any 30 caliber pellet gun for back yard fun. ... felix

[saz]

Saz drug me into the 300 madness. Got a barrel, bolt, reloading dies and brass, waiting for me to get home. I will be watching this thread with great interest also

Sorry man, but you started it...... HAHAHAHA!

[wlc]

Just got to really shoot mine a good amount today. Loaded with J bullets. It shot pretty good at 50. Haven't measured yet, but less than an inch at 50 if I throw out the called fliers. Loaded with 1680 and either 208gr AMAX or 225gr BTHP. Got to drop my load just a tad as most were just supersonic in my rifle with a can on it. I had three I had loaded with 190gr Hornady spritzers over a charge of RL7 just to test for function etc. Those sounded like a pellet rifle and cycled my carbine gassed action with bolt lock back on the last shot. I like the round and really like the quiet of having a can on the end. I really am of the opinion that every firearm sold should come with one as standard equipment.

ETA: Factory Rem subs don't shoot worth a darn in my rifle. Not accurate at all and often have a fail to feed and not lock back the bolt.

[usmcscout]

467

http://www.castpics.net/subsite/TopPunches/Lee.html



2400 is a great powder and does well in a bolt gun but as you discovered it is too fast to provide enough gas volume for reliable functioning.

well thats my prob I have been fighting find good load stoped at like 18 gr or so with 147 gr mil surp pulls and an old ideal mold 180gr acurite as hell in my rem 700 .308

so now I can give up on 2400 I was thinking I was doing something wrong thanks jailer

[Moonie]

I've had great luck with the Lee 312-155 over 15.3gr of W296/H110 (about 1,850fps) and 245/247gr NOE/Accurate mold over 12gr RL-7 (about 1,200fps, if memory serves me correctly)

[DanWalker]

Has anyone tried H335?

[felix]

On the agenda. ... felix

[saz]

The success of certain powders is directly linked to the burn rate in relation to the length of the gas tube correct? If so, where is that happy place with faster powders? 2400, 1680, Lil Gun etc? Faster powder, shorter tube? I am sure it relates to supers vs subs also.......

[Jailer]

As Felix has mentioned before, if you know you are going to be using faster powders and boolits go with a pistol length gas system and an adjustable gas block. It will give you maximum flexibility in powder choices. Lilgun is about as fast as you can go and still get reliable functioning with supersonic loads in a carbine length gas system.

[MGySgt]

AA1680 and H110 work well in a Carbine length gas system.

[DanWalker]

I would think you would need a larger gas port to see any effect from an adjustable gas block. A regular gas block allows full flow from the port anyhow right?

[Jailer]

I would think you would need a larger gas port to see any effect from an adjustable gas block. A regular gas block allows full flow from the port anyhow right?

In a carbine length system yes you would. In a pistol length system the gas port is located closer to the chamber producing a longer pressure pulse from increased dwell time. With supersonic loads you can easily over gas the system. If you add an adjustable gas block to a pistol system you can limit the amount of gas for supersonic loads with slower powders and open it up for faster powders like the OP was trying to do.