Bear & Moose Whacker Upper

[Cgrutt]

OK I'm confused. Are you talking upper for AR? $700? I'd love to be in but can't afford it at the moment. Interested though and bonus time is coming next few months...

[Meketrefe]

There is time C. We will have to phase this out based on availability of parts. And then we have to have the test barrel tested first and then order to cut the barrels the same. So there is time.
A cat takes a few months always if not more.

[BuellSix8]

GREAT!!! we are finally getting some traction. This way cost per barrel / bolt comes down for everyone.

how many? one for starters and another one for pistol?

Yes actually.... Since I have a lower on my permit I'm decreasing my rifle stock. Plus I have an extra LWRC Six8 upper that could use something different.

[BuellSix8]

Thinking .750 gas, midlength in pistol 10.5" or smaller like 7.5-8.5" in pistol gas ?

[Meketrefe]

Thinking .750 gas, midlength in pistol 10.5" or smaller like 7.5-8.5" in pistol gas ?

When the time comes to put the order I can order a 9" if you want. I wouldn't go smaller than that. That should be fun!!

[BuellSix8]

9" would be perfect actually.... and thinking 18" rifle gas or 16" midlength for standard barreled upper?

[Meketrefe]

9" would be perfect actually.... and thinking 18" rifle gas or 16" midlength for standard barreled upper?

What about 9" and then 17.5" or 18" that is the remaining from a 27" barrel stock before profiling and chambering?

[WARFAB]

Too late to suggest 357 Mayhem?

I'm trying to follow this thread and unsure of where things have ended up. Is this based on a .308 case?

[Meketrefe]

I started with the 308 case but then it was too much power so I came up with similar geometry based on the russian bolt head so 7.62x39, grendel and such....

[WARFAB]

Is it overall speed or rotation that causes bullets to disintegrate? Could higher velocities work with a lower twist rate? Stabilization is determined by RPMs more than rotations per inch, but I haven't done the research to see if you could stabilize at the velocities you've predicted. Obviously the stabilization would vary by bullet size.

[Meketrefe]

The goal has been to make this to be super versatile so it would take pistol bullets as wells as some heavy weight 358 rifle bullets. But bulk pistol bullets are not designed to be shot at 3000 fps+ per second and we can also use the shortened case to shoot some heavier more efficient bullets for hunting like the 200gr FTX that is a great price from hornady. So I went from 1.6 case OAL to 1.5" with a smaller radius. So this way we leverage both pistol and rifle worlds. Bonded and solid pistol bullets like the barnes and cop would do fine even at 4000 fps if one could do that but we are not going to hunt Buffalo to Africa with this and we want to make sure we have still a pleasant fun shooting with affordable bulk bullets but also it can take up to 220gr sierras that is an amazing moose and bear bullet, even a large brown bear that we do not have many around here anyway. But an affordable 180gr or 200gr FTX will drop deer, mule deer, elk and moose like it was hit by lighting. Also the 158gr 357 hp bulk bullets as well as some 9mm bullets.
hell, we could use our 9mm bullet bullets given we run the residzng mandrel for 9mm and it will shoot them just fine at amazing speeds. Those like 124 grains will be great for short ranges up to 200 yards too. We are not inventing anything here really. we are making a multipurpose round run on the AR that is super fun and super versatile and potentially for the same or less cost of shooting bulk 55gr bullets for practice or moderate short range with double the horse power than the rather anemic and still expensive 300 whisper / blackout.
A 9mm/357 hp at 100 yards shot at 2800fps will make a basketball size wound cavity. We will have to test to see which ones do not ruin so much meat for deer or even chop them in two halfs. Probably a more stout one with more penetration and less broad wounding.
One way or another those should be accurate for fun practice and for hunting they will be like injecting brutal grenades assuring DRT no doubts.
1:14" twist is the 358 bore standard that should stabilize up to 275grs but those heavy bullets do not make sense other than subsonic or ultramagnums that is what the 275 and 300 grains are designed for. And they are too expensive anyway. But we could shoot more affordable 250gr supersonic or subsonic. The recipient is not going to notice much the difference. I prefer flatter shooting and the options are so much better. But I will try the 225gr sierras and others just for fun.
What I really like is the idea of big bangs w. 147 or 154 super affordable bulk bullets. I have several brands to test speed, trajectory and accuracy. Later we will test terminal lethality but they should be all pretty brutal.

[BuellSix8]

While we are on the subject of loading this beast... what are we thinking for powder? H4198, H335, 10x,...?

BTW Def digging the idea of a 9" paired with a 17.5" / 18".

[Meketrefe]

While we are on the subject of loading this beast... what are we thinking for powder? H4198, H335, 10x,...?

BTW Def digging the idea of a 9" paired with a 17.5" / 18".

I think I am going to do the same. I think we loose some speed but it should be fun to shoot 180grainers at brutal speeds.
powders should be in the: H110, N110, lil-gun, reloader 7 etc... So it is a faster burner. but will also use other powders like 1980 and even faster like longshot with 9mm and 380 bullets!! LOL but not sure this will need special to cycle but we will find out what to do. you wait for my test barrel.
I think the b!tch like always is going to be the bolts as I have shortage of ARP superbolts. To me this is key. We need superb parts here. Otherwise we will have to adjust our shedule to abailability of parts and start with one upper and later get the 2nd. I am trying to get some extra 800 bolts that is another reason that turned me away from the original 308w bolt face. But H. at arp is hard to get to get some of these running.
Still there is another option that is the 358 MGP they have there but I cannnot afford more expenses right now and I want more power anyway! lol.

[BuellSix8]

Yea I've been following the 358 MGP threads as well.

We need superbolts in 7.62 or will the 6.8's work? Those 800 bolts look like Bad mothas

[Meketrefe]

the 6.8 is too small. I started wiht the 308 but then decided on the LBC bolts he has. That is the same as 7.62x39 that means more capacity.

Early prototype (similar to the final just a bit larger)