Good load for my new 8" PCC in 9mm

[Marshal Tom]

Hi, just had built a New Century Arms, 8 inch PCC that takes Glock mags and has last round hold open. The thing is just so much fun to shoot. I have been trying to work up a load for it. I had been using 115gr. XTreme bullets that I load for my semi auto pistols. I was not having great success with accuracy. I went back to the shop and my friend said that they have a 1/16 twist and that they prefer heavier bullets. He told me that 124gr or 148 would be better. I then ordered 148gr. X Treme's and tried those out.I am using CFE Pistol right now. It has a Holosun dot on it with Magpul backup sights. I love the thing but looking to make it shoot tight groups.

 

[venomballistics]

You're using a plated bullet.
Back your crimp off till it just makes the plunk test.
Plated don't jive with being over crimped

 

[Ivan the Butcher]

Not quite the same! When I had a full auto MAC-10 9mm The best accuracy from the 6" barrel was with 147's and WW 231 (very similar to CFE Pistol). At 50 yards 4 and 5 shot bursts were in the 3" group size from the kneeling position with the suppressor. and about 6" without. I loaded them to about 950 fps. Almost all factory 147 ammo is subsonic and is much easier on the senses!

From time to time 158 grain jacketed soft points in .357" would be on sale and I load a batch of a few thousand. In the 900-1000 fps area they are very accurate and have higher energy. (very noticeable on targets that fall down or fly away!)

When I was in my 20's, lots of bullets in a burst was "Fascinating!" However, when I was in my 50's, one shot, center target at 500 or 1000 yards was so much more fun. 9mm won't do that! You can expect your tastes to change over time, go with the flow!

Ivan

ETA: The Accurate powder has good data on 38 special bullets in the 9mm Lugar cartridge.

 

[OutAtTheEdge]

Not quite the same! When I had a full auto MAC-10 9mm The best accuracy from the 6" barrel was with 147's and WW 231 (very similar to CFE Pistol). At 50 yards 4 and 5 shot bursts were in the 3" group size from the kneeling position with the suppressor. and about 6" without....

Ivan has to be the only person I've ever heard of to do burst-accuracy testing on a select-fire MAC-10. Hat's off to you, Brother! I always just went for "accuracy through volume" when the switch rolled over to the rock 'n roll setting.

 

[venomballistics]

My build is 16" ....
In my case, I found it beneficial to go to slower burn rates.
So far, HS6 and AA7 are the plan A and B of the show. Plated has not been great.
Crimp management helped, as did slower powder, but I was never happy.
Subsequent dev work was with Hornady XTP's in 115 and 124.
115 was slightly more accurate, but function suffered.
The data gleaned from this test series lead to the Lee 120 mold and powder coating
I still have load adjustments to make, but out of the gate, it's beat out any of the plated by Berry's, or zero.
I'll revisit CFE Pistol at some point for handgun use.
The carbine doesn't like the stuff

 

[Nevada Ed]

My 147 gr 9mm bullets seem to like Unique for the best groups but it is hard to find,
so if you have a little faster or slower powder, give t a try and see what happens, in the 850 to 900 fps areas.

 

[3rdgeargrndrr]

Possibly slug your barrel and get appropriate bore size.
I have found cfe pistol and blue dot to very accurate out of my 10” PCC faxon bolt and barrel.
I dont have the twist rate off the top of my head but im looking at 3” groups offhand just casually plinking at 15yds using Hoosier coated .356 147grn, CCI, mixed brass and w/ CFEP 4.1grain as the best load. (Forgot the OAL)
Ive never really cared about precision shooting with it yet, it just gets to eat whatver loads i have from my other guns pet loads.
Agree on crimping just to bring the case mouth back and not overcrimping.
The AR PCC is such a hoot, everyone loves shooting it.

 

[venomballistics]

Possibly slug your barrel and get appropriate bore size.
I have found cfe pistol and blue dot to very accurate out of my 10” PCC faxon bolt and barrel.
I dont have the twist rate off the top of my head but im looking at 3” groups offhand just casually plinking at 15yds using Hoosier coated .356 147grn, CCI, mixed brass and w/ CFEP 4.1grain as the best load. (Forgot the OAL)
Ive never really cared about precision shooting with it yet, it just gets to eat whatver loads i have from my other guns pet loads.
Agree on crimping just to bring the case mouth back and not overcrimping.
The AR PCC is such a hoot, everyone loves shooting it.

Currently, I'm getting <3" @ 50.
I'd like to wrestle a little tighter out of it still.
You're right about the AR platform PCC. Being fun to shoot.
The way I see it, accuracy detracts from it's enjoyment in no way whatsoever, but it does add to its utility.
I liked the idea of a 9mm carbine since the marlin camp carbine flopped. I've always wondered why it wasn't more of a mainstream offering through history.
Ideally, I think 100 yard goals would be appropriate.
Well tuned for such, it becomes a logical constant companion.

 

[jschmidt]

Are we talking about an AP-5? If so, 124 grain. 148s are subsonic and good with supressors.