View Full Version : My new project.

May 04, 2017, 22:10
Nothing new in the wildcat realm, but here is my ode to Mr. Ackley. Basically a 7.62x39 Ackley improved for a .308 bore. A friend bought a Blackout, but was disappointed in the performance with 150's. He was casting about for a round that was friendly in the AR-15 and would put 150s out at 2400+. Seems like there are a few decent cartridges that do this, but he didn't want to be beholden to a proprietary round that cost $1.50 each, wait around for Grendel brass to get available at less than .70C each ( and then neck up and load a .20C bullet and shoot to get good brass) or trim/form/blow out the shoulder, etc. Why not improve a fairly common 7.62x39 that we can get for 50 cents a round loaded in bulk, shoot it up practicing, training, at prairie dogs, etc and load some decent hunting ammo for hogs/deer, etc with the resulting brass. In testing so far, these feed pretty well out of the mags I can get my hands on in newly californicated Colorado. (5, 10, 15 rd grendel and 5, 10 rd 7.62x39) Brass life should be better, great selection of bullets, we lose a little length in firing, so trimming will be deferred a while, bolt thrust should be somewhat less due to the straight case walls, feeding should be better in the AR mags, we gained 3 1/2 grains water capacity, and it just looks cool. The main concern I had was an Ackley in a semi-auto. With the Ackley treatment, the bolt needs to have a little bit of crush to properly headspace. Chambered a barrel last night and it seems to function well with the original round. Now to the range to obtain some real fire-formed brass and see what this thing can do. Of course, we aren't expecting 308 Win ballistics, but it looks promising as an AR15 hunting round.

May 04, 2017, 23:15
Best of luck to you. Like to see people tinker. About over my wildcat days as most of the wildcats have used and embraced have gained much popularity and are almost mainstream like 7mm Practical, 338-06, 22-250 Ackley Improved, 25-08, 257 Roberts Improved and a few more. Am a sicker for quarter bores, 7mm's and 338's. Nothing can be done with 30 caliber much that hasn't so double props to ya. Keep us in the loop.Have tons of x39 boxer primed brass. You going to play with any heavies for subsonics?

May 05, 2017, 19:01
Huey, Thanks. It seems there is nothing new under the sun. We might just find out during this project why it never took off as an idea, bu I like what I am seeing so far. We will see what it will really do tomorrow. Range day. Seems people have been talking about it for years and years. Some have done it, but there is not a whole lot online about this specific situation. It must be in the DNA of the American shooting public to do it our own way, and I love that. There is something for just about everybody if you investigate the options. I have a 250 Savage AI, and it is a great little lightweight in a M7. I have a 338-06 AI in the works, too. It has been for a while, but I might just get motivated enough this year to finish it.

As for subs, we are going to be using a 7 or 8 twist, and I had the reamer ground for 240 MK's at mag length, so it is a possibility, but we are concentrating on bullets in the 150 range right now and are curious to see if overstabilization will be an issue. I have not seen it too bad in the past, and these will be hunting guns, so I think we will be fine. We both have Blackouts and that is already about perfect for 240s at 1100.

I'll post some results one of these days.

Thanks again.

May 08, 2017, 07:48
So we only had time enough for a few handloads, but we learned a lot at the range Saturday. We need to refine the port size a little, but I think we are getting it. 16" bbl was a little overgassed, as it was a blackout barrel with a big port at the carbine location. It cycled probably 90% with the PPU soft point round nose factory round. better than I thought it would. We neck sized at the range and function was nearly 100%, with the handloads. Factory x39 bbl re-chambered was a single load prospect as it was rifle length and had a smaller port. I think when we get dies, full length sized cases will be working great. Several bullets we tested will seat to mag length and have the cannelure at the right spot. We didn't get to do much for velocity testing other than the factory ammo out of the new chamber as the chronograph acted up a little but it looks promising. Hopefully more to come soon.... although with the wait for custom dies, maybe not too soon.. :o/