284 Winchester Vs. 7mm-08 in shorter barrel

[huntersedge89]

So I have an extra 7mm blank and was thinking of building shorter barreled rifle in 7mm-08 or 284 Winchester. I would like to keep it around 22" or so, would I gain very much going to a 284 over a 7mm-08 in a barrel this short? Anyone have experience with both of these calibers in shorter barrels? I would expect them to lose a similar amount of velocity per inch of barrel length lost, but I could be wrong. Also do you think it is worth putting a 284 in a SA receiver or do you loose too much powder capacity?

 

[GLB]

No experience in the 284 with a short barrel but the short barreled 7mm08 works very well.

 

[huntersedge89]

No experience in the 284 with a short barrel but the short barreled 7mm08 works very well.

Thanks, what barrel length were you running on the 7mm-08?

 

[Xshot]

What's your over goal?

I just completed my 7mm-08 AI. My goal was to build a hunting rifle and to keep the weight (less optics) under 7.5 lbs. I achieved my goal with the following:

Stiller Predator action w/Picatinny rail
Rock Creek #4 sporter (23 inches, fluted and threaded muzzle)
B & C Alaskan II BDL (Devcon bedded and camo painted)
Wyatt long (2.95") mag box

FWIW - I very happy with the entire package. Rifle is shooting factory Winchester 140 grain PP sub MOA @ 100 yards. Once I'm done fire forming brass, my plan is to create some hand loads with CFE-223. I hope get some get impressive accuracy and velocity with this combo - time will tell. Current optic is VX-R Patrol 3-9x40 TMR. It's a nice light scope and puts the entire package right at 8.5 lbs. Note - I did need to hog a lot of material out of the stock barrel channel and re-contour it with resin micro-balloons. It was a lot of work, but it paid off nicely. Plenty of clearance for FF and cooling of barrel.

 

[turbo54]

While I've no experience with shorter 708s, a fundamental truth is the more overbore a cartridge is, the more it needs a longer barrel. Another way to think of it would be the slower the powder required, the more it needs the longer barrel.

I've found my short action 284 loses ~45fps/inch between 27" and 30" using H4831sc and 175smk.

Will a 22" SA 284 outperform a 22" 708? Yes, but not by much. Probably ~50fps or so.

I load my 284 cartridges to 2.950", at the limit of what my action/mags can handle. Yes, it takes away some capacity, but not too bad. My 28" barrel goes 2835fps with 54gr H4831sc and the 175. This is a moderate load.

That said, a 2.950" 708 cartridge would outperform a 2.800" 708 cartridge by a decent margin also.

Bottom line: The 284 will outrun the 708 all other things equal, but it'll be almost imperceptible until 800+ yards with high BC bullets. I would stick to the 708 due to brass availability, marginal gains, and better barrel life.

 

[GLB]

Thanks, what barrel length were you running on the 7mm-08?

I have a 20" krieger and it hammers. I have a new load for it using the berger 140 VLDs, not sure of the velocity but the way it hits steel it's got some.

 

[mkollman74]

While I've no experience with shorter 708s, a fundamental truth is the more overbore a cartridge is, the more it needs a longer barrel. Another way to think of it would be the slower the powder required, the more it needs the longer barrel.

I've found my short action 284 loses ~45fps/inch between 27" and 30" using H4831sc and 175smk.

Will a 22" SA 284 outperform a 22" 708? Yes, but not by much. Probably ~50fps or so.

I load my 284 cartridges to 2.950", at the limit of what my action/mags can handle. Yes, it takes away some capacity, but not too bad. My 28" barrel goes 2835fps with 54gr H4831sc and the 175. This is a moderate load.

That said, a 2.950" 708 cartridge would outperform a 2.800" 708 cartridge by a decent margin also.

Bottom line: The 284 will outrun the 708 all other things equal, but it'll be almost imperceptible until 800+ yards with high BC bullets. I would stick to the 708 due to brass availability, marginal gains, and better barrel life.

Great answer...

 

[19Scout77]

I shoot a 22.5" 7wsm. While i burn a pile of powder doing it...I shoot 162 amaxes at 2955 and 162 bthp even faster. It would require a bolt face mod, but is another option.

 

[santee116]

Here is a link to a .284 with a 22" barrel that just sold in the for sale forum.

http://www.snipershide.com/shooting...ce-built-mountain-tactical-rifle-284-win.html

He reported the following with a 162 Amax :

"This gun will shoot in the .3's when loaded with 4831SC or in the .5's loaded with RL17. I chose to utilize the RL17 for the added velocity with more than acceptable accuracy for what I wanted to accomplish. It would shoot 2846fps with the 4831SC and 2942fps with the RL17."

Not bad for a model 7 short action, if you ask me. But I probably wouldn't go shorter than 22" with a .284 win. Anything shorter I would just go 7-08.

 

[huntersedge89]

Thanks for all the input! Right now I am thinking I will build a 284 if I go with a long action and a 7mm-08 if I go with short action. The barrel I have is a 1-9.5" so I don't really plan on shooting anything over the 162 a-max out of it. Seems like the 7mm-08 might be the best choice as I will primarily be shooting the lighter bullets for hunting and the 162's for targets. 284 seems to have a bigger advantage with the heavier bullets, which probably wouldn't shoot very well out of this barrel anyways. All that being said I am already set up for reloading the 284, but brass seems pretty hard to find now.

"This gun will shoot in the .3's when loaded with 4831SC or in the .5's loaded with RL17. I chose to utilize the RL17 for the added velocity with more than acceptable accuracy for what I wanted to accomplish. It would shoot 2846fps with the 4831SC and 2942fps with the RL17."

Are these common velocities out of a short action 284 with a 22" barrel? They seem pretty fast, I've read of numerous people getting around 3,000+ fps with the 284 and 162's on a LA with RL17. If I could get velocities that good maybe it would be worth it to step up to the 284 on a short action.

Basically I am looking to build rifle around 8-10lbs with a shorter barrel for hunting and some target shooting while not get too long with a suppressor on the end and not compromising too much on the velocity.

 

[GLB]

Mine has a 9.5 twist and I think that is a good match for the 140 grain bullets.

 

[huntersedge89]

Mine has a 9.5 twist and I think that is a good match for the 140 grain bullets.

Thanks, Yeah I was thinking of shooting something in that range for my hunting load.

Does anyone know off hand know about how much weight a LA Remington 700 receiver adds vs a SA? All other things being the same (stock, barrel contour, etc.)

Also anyone running the Accurate short magnum mags or the Alpha Type 3 Magazine with the 284? Would one of those give you enough added OAL to make the 284 a better option in a SA?

 

[turbo54]

Also anyone running the Accurate short magnum mags or the Alpha Type 3 Magazine with the 284? Would one of those give you enough added OAL to make the 284 a better option in a SA?

I'm running my 284 out of Alpha type 3s. They advertise 2.985" COAL, but 2.950" is more like it. They claim the type 3 and 4 will work with 284, which is a half truth. They can be MADE to work, but require grinding/fitting of the follower to match the further-forward position of the 284s shoulder as compared to the shoulder placement of the WSM cartridges. Also, the feed lips took a lot of tweaking to get reliable feeding.

2.950 is much better than 2.800", or even 2.850", but it still kind of sucks. You give up a little case capacity, but also you're forced to seat bullets way down below the neck/shoulder junction with all but the lightest bullets.

Never again will I configure a rifle/cartridge that seats bullets below the NSJ; its nearly impossible to maintain true consistent neck tension, and donuts will fuck you in the ass.

EDIT TO ADD: I might also point out that 7mm-08 will also have the 162s and 175smk seated down below the NSJ if COAL is less than ~2.950". A bummer.

 

[Hunt4life]

Great thread, I think my next one will be a 20" 7mm-08 shooting the 162 amax when they are available again. Want a shorty.

 

[Sniper260]

Id go 708 for the short barrels. Its a proven fact that a 308 does just fine with a shorter barrel.. and the 708 is a knockoff of it... thatd be my choice..

 

[usmc45]

After hearing you guys that have first hand knowledge of these rounds, to me it seems as though both of these are a compromise (maybe not, I don't have any experience with either) Is there something that falls in between these two?

 

[Graham]

There's nothing between a 7-08 and a .284. The 7-08 won't give you velocity, so you have to rely on BC. The .284 will give you the velocity you need, but not the speed of a magnum without a long barrel. Neither are very good in short barrels because neither case has enough powder capacity to trade length for velocity without going to faster powders and light, low BC bullets.

 

[Hunt4life]

After hearing you guys that have first hand knowledge of these rounds, to me it seems as though both of these are a compromise (maybe not, I don't have any experience with either) Is there something that falls in between these two?

No, not really. 7mm-08 is the true choice unless you reload and want to scavenge or reform brass. Too bad as the .284 is bad ass and was way ahead of its time.