Home Forums Hunting & Shooting Custom Rifles & Wildcats Cartridge selections for a short barrel build

I have a 7mm Hart # 3 contour barrel that I bought here and have decided I want to go ahead and do something with it. The barrel is intended to be for a short barrel rifle, I guess it would be considered a carbine? The finish length will 21” from the muzzle and the flutes would stop at 2 inches from the end, I may be able to do 21.5”but that is max for my own personal aesthetics as I would not want the flutes stopping any further from the end than that. I could be talked to even going down to a 20” barrel too as I think that would look even better and the flutes would stop 1” from the end.

I have three options of donor actions I could use for a build.

1. I have an older model LA Weatherby Vanguard that came with a McMillan stock. These stocks are perfect for this as it fits me well and has a shorter forearm. It is presently in a 270 and I have just downloaded 150 gr. bullets to around 7x57 velocities. Since this is a LA I thought about re-barreling to a 7x57 or maybe .284 Winchester, also a 7-08 or 7-08ai but since we are talking a 20 or 21” bbl. to go AI seems pointless. I do like this McMillan stock and want to do something with it but those 150 gr. 270 partitions at 2600 fps are working just fine.

2. I also have a Howa 7mm-08 sitting in a Hi-Tech (Bansner) stock. I could re-barrel to another 7mm-08, .284 Win or 7x57 since this is a SA I would assume the 7mm-08 or 284 would be the most logical if I went with this action?

3. Last option is I have a Remington 700 7mm saum and a classic McMillan stock I could build on but I am not sure if another 7mm saum and this one with only a 21” barrel make sense here either?

Decisions, decisions???

option #2 in the 6.5 creedmoor

7.0 creedmore...

Short cartridges in long actions suck. Dont do that.

Sounds like a mish-mash of parts / combinations, and you're trying to find a way to cobble them together...

I'd be finding a donor short action that I liked, and finish the bbl at 20 to 21" in 7-08AI. Would work well. But as you've already got a Howa 7-08 one of them may end up redundant.


Maybe sell your parts and unwanted stuff and have a custom made just as you want it is the best option. You'll never regret having a rifle made to your exact specs.

7mm barrel is what I got so I am looking for 7mm cartridges only

bobnob17,

It does appear that way. I have often wondered about a 284. I have never had one or knew anyone that did but I wonder if I built a 284 in either the LA or SA with a 21" barrel shooting 140 gr. bullets what kind of velocity I would truly get? I have always read it is a Short action 270, and I am big on the 270, so a true real word short action 270 sounds great to me.

Go with the Howa action and chamber the barrel in 7mm Bench Rest.

If you put a 284 Winchester in a 21" barrel, you will better the ballistics of a 7mm-08 by an honest 200+ fps., depending on load and bullet weight. You should easily match the ballistics of the 280 Remington.

7x57 Ackley

A 284Win would work well too. I reckon 21" you'd get around 2900+ fps with 140-150g bullets. Gonna have some blast and noise of course.

FWIW I like the idea of a 284 on one of those "intermediate" actions like the MRC does. Would allow you to seat bullets out to a decent length without wasted mag box space...

Your 7mm bbl mated to one of those cut to 21" would be a powerful yet compact package, with just enough weight to curb recoil.

I wouldn't over-think it.

for a 21" barrel 7mm, I'd go 7-08 on a short action or 280 on a long action.

There you go Shane, getting all practical!

I'd be more interested in twist rate/bullet choice.

The barrel is a 9" twist. I am thinking 139 gr. GMX or 140 gr. TTSX for a one bullet answer for all game I would shoot with this rifle. Of course the 120 gr. BT's & TTSX would work wonders too.

That should cover a lot of ground, however it gets chambered.

Sinnce you haven't had a 284 Win., a couple of notes. One is unless you reload (which I suspect you do), there is 1 factory load choice and can be hard to get. Then, I have shot 3 different 284's-2 in Win 100's (still have 1 of those) and the other was in a Ruger 77. And all of them have been punishing. But I love the caliber. The 77 surprised me as I have shot a 7 Mag and presently have a 264 Mag in the Hawkeye and neither have come anywhere close to the recoil of the short, fat cartridge. All that to say, in a lightweight rifle, it is possible it will be uncomfortable to shoot much on the bench. Or that is my $.02 worth

Why not cut the barrel on #2, see what it does, and contemplate the other barrel for another build on an action that isn't already mated to a 7mm barrel, or trade that barrel for one in 6mm or 6.5?

Yep, easy peasy.

Sounds like you purchased my old barrel. That was originally intended to be a 7mm-08AI before I decided I wanted a lighter contour and a longer barrel. Given your options I would build a 284.

David