Thread: Ultimate compact rifle & catrige - 6mmGT/22GT in howa mini action

I've been following this guy's rifle built, a 22GT: https://ultimatereloader.com/2022/02...art-to-finish/
All customized as those American do, while in NZ most of us can only dream about those things. Then I suddenly realized we have one perfect action for it, the Howa Mini. the GT has bolt face of 0.470, while howa mini largest caliber 7.62x39 has bolt face of .445, it should work I think. Also the existing magazine should work too, as the case has shorter length than 223. This will leave 6.5gredel in dust...
Surely someone will give it a go

Interesting watch

Here I'm holding a .308 case (same bolt diameter as GT), there should be plenty meat on mini bolt to accommodate the case

https://www.nzhuntingandshooting.co....23-deer-64884/

Originally Posted by gimp

https://www.nzhuntingandshooting.co....23-deer-64884/

which page you want me to look at, gimp? there are 53 of them. lol. If you are advocating not to use 223 for deer, I agree with you. But a 6mm/22GT has case water capacity of 43 gr, comparing to 30gr of 223, so we are talking about a very different beast here.

Originally Posted by hey

which page you want me to look at, gimp? there are 53 of them

53 pages of the .223 being effectively demonstrated to be the most practical ultimate cartridge of any size, let alone compact.

not sure about that claim. I have shot a fallow with 69smk at the range of 50M, hit in the lung, watch it bolted. Then spent quite lot time to track it down. It is dead about 50m away, but in the thick bush it is very difficult to track it, no blood trial at all. I've also watch a friend shot a red hind with is 223, again it hit the chest, same thing, bolted and that time we could not find it. I agree shot placement here is the key for 223. but more speed/energy can't go wrong

You'd get a similar experience using a bullet that doesn't work in any cartridge. I'd recommend selecting a bullet that works.

Well none of that is any fun

Originally Posted by gimp

53 pages of the .223 being effectively demonstrated to be the most practical ultimate cartridge of any size, let alone compact.

What a hater ��

The Howa Mini magazines will be a bit limiting when it comes to long bullets in the 22GT.
Using a shorter bullet should work ok but the long high BC bullets are what gives the fast 22s their edge when compared to 6mm/6.5mm cartridges.

I’d imagine the GT case would be good for an additional 300-400fps over 223 but with lower BC bullets I don’t think the ballistics would be that much better over standard hunting distances to be worth the effort. Not at realistic hunting ranges anyway.
The real low cost option would be to ream a 223 out to 223AI, which would have the benefit of being able to use 223 ammo and give a bit better FPS.

I’m sure you could do the conversion and get decent performance but it’d end up being a lot of mucking around.
If you end up getting into a situation where you are re-barrelling the thing then I’d just go a 22 Creedmoor (non-mini of course) with the shortest barrel you can get away with, or 22-250 if you want factory ammo.

Originally Posted by Beetroot

The Howa Mini magazines will be a bit limiting when it comes to long bullets in the 22GT.
Using a shorter bullet should work ok but the long high BC bullets are what gives the fast 22s their edge when compared to 6mm/6.5mm cartridges.

I’d imagine the GT case would be good for an additional 300-400fps over 223 but with lower BC bullets I don’t think the ballistics would be that much better over standard hunting distances to be worth the effort. Not at realistic hunting ranges anyway.
The real low cost option would be to ream a 223 out to 223AI, which would have the benefit of being able to use 223 ammo and give a bit better FPS.

I’m sure you could do the conversion and get decent performance but it’d end up being a lot of mucking around.
If you end up getting into a situation where you are re-barrelling the thing then I’d just go a 22 Creedmoor (non-mini of course) with the shortest barrel you can get away with, or 22-250 if you want factory ammo.

Good point Beetroot, probably the 6mmGT is better suited. I went to the GA precision site(who invented the cartridge) and the reamer they are selling has the freebore of 0.12", which is quite long. it will definitely seat further out than a standard 223 and probably over the mag length. I will order a customized reamer with less freebore if I ever want to build a one. I won't bother with those AI cases, not worth the trouble just get 1-2 more grain in.

Howa do a mini in 204 Ruger....
That fits the bill straight from the factory.
Lead Laser beam.....

Admittedly probably limited to head shots though

The Mini comes in 450 Bushmaster. That's based off of the 284 Win case and has the same .473 head. So it'll have a 308 bolt face.

That said, the bushmater has a pressure limit of 38,000psi which will limit the bolt thrust. I suspect there's a good reason that the engineers at Howa haven't chambered the mini in any high pressure 308 bolt faced cartridges like 6BR (other than the mag length being an obvious limitation).

Just forget the rest and shoot a 22-250. My first and still my favourite calibre