Converting my 7mm mag?

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Hey all

I have a remington 700 BDL in 7mm mag. It is a beautiful rifle and is new as far as I can remember. I bought it for a used price but couldn't remember if it had been shot and if it did maybe a couple rounds. I would have to look again. My father has it in his safe for the past 7 years and I haven't seen it since I bought it(gone in the military). So I basically forgot everything about it.

I am not familiar with gunsmithing as far as what calibers/actions can be converted. I would like a heavy hitting caliber. I would like to know what my options are for larger calibers.

And yes I have considering selling or trading.

Thank you
Casey
 
You can convert the existing action and barrel to any chambering that uses the same boltface diameter and uses 7 mm or larger diameter bullets in a cartridge no longer than the 7 mm Mag. There are shops that will rebore and rifle the barrel for larger bullet diameters if you want to wildcat the 7 mm case to one? You can also get an entirely new barrel chambered.

The action's bolt will open will only so wide to allow cartridges in. You will have to limit your choices to that length. If you don't want to change the whole trigger guard and floorplate and magazine assembly, you will also have to limit yourself to what the existing magazine's length will allow? That's why I said the new cartridge couldn't be longer than the 7 mm mag, though your gun might have a little more room? You'll have to look.

All this having been said, the 7 mm case has roughly 10 grains more powder capacity than a .30-06 and about 25 more than the .308, putting it right in between these rounds and the .300 Win Mag for potential energy. So, it is already a pretty hard hitting round. I saw mention (but have not verified) of a statistic claiming large game is taken on the North American continent with fewer hits (2 on average) using .30-06 class cartridges than are needed shooting the big whammers (more than 2 hits on average). The explanation, if it is true, would be speculative. It could be the big guns just make more shooters flinch badly, given that accurate shot placement matters much more than cartridge size to getting a rapid stop?

Also, lower penetration is possible. Garrett's and Linebaugh's web sites, among others, describe instances of higher velocity rounds getting less penetration than slower ones using the same bullets. This is in test media. It is not explained, though I know the force acting on a bullet's overturning moment increases with velocity. Even if not actually tumbling, this means faster bullets would have a harder time staying aligned with their path through a medium, thus exhibiting higher drag. So, there seems to be a maximum penetration velocity for each bullet design.

Bottom line, you may already have something that will do what you want? Maybe not? It depends on what you intend to do with it, but keep that in mind before paying for a change.
 
Thank you for the information. I was just looking for a different caliber to shoot. I have a .270, .308 and many others between my father and I. Biggest cartridges being a .300wby mag and a .300win mag.

I thought I saw somebody doing a .375ruger off of a 7mm rifle. I didn't know if I could go up to a .375H&H or something with this rifle?

Just looking at other options. Though it might be just better to sell and buy something else. Just such nice rifle, wood and all.

Thanks
Casey
 
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7 mm

Sir:
Keep that good 7mm rem. mag. and buy a 8mm mag. or a 375!
The 375 is best choice if you ever plan to go to Africa. Buy A-Square bullets, the "dead-tough or monolithic solid."
If you like the 338 go to the 338X06! Or the 338 WM. The 338X06 would be a smaller bolt face size. And, by all means get a "Limg-saver" recoil pad.
Harry B.
 
Everyone seems to make a small deal out of reboring and rerifling a barrel, but it is not a normal gunsmithing job. There are very few places that do it and they are all backed up to about three weeks after Doomsday. It will be a lot cheaper to have a new barrel installed, and a lot more practical just to trade the rifle on one in the caliber you want. FWIW, I don't know where you live and/or hunt, but 7mm Magnum will take care of about anything on this continent.

Jim
 
I will most likely trade it or sell it. Its not that it wont take care of mostly everything on this continent. It's that I want a different caliber to shoot. In my mind the 7mm mag is a glorified .270. This comparison is based off of factory loads. If you look at the 140gr and 150gr bullets the .270 and 7mm are almost identical. The only advantage the 7mm has is able to load 175gr bullets. Look at winchester's 150gr SP's. At 500 yards the difference in energy is only 25 pounds and velocity is only 20fps to the good for the 7mm. When you look at the 140gr loads some .270's actually out perform the 7mm.

What I am trying to say there is nothing my 7mm can do my .270 can't. So I just want something else to shoot for the sake of shooting, hunting(bigger or larger game whether it be here anywhere in the world) etc.

As far as a .338 I have been wanting a .338-378wby for sometime. I just love everything about it. Its one of my favorite wildcat cartridges. Its energy and velocity at long ranges are amazing.
 
Remington 7mm Mag is in the family of belted magnums based on 375H&H Magnum.

.264 Winchester Mag, .275H&H Magnum, .300 Winchester Magnum, .300 H&H Magnum, .338 Win Mag, .375H&H Magnum, .416 Remington Magnum, .458 Winchester Magnum.

I think there might be a .35 Remington mag in there as well as some others.

Remington 7mm Magnum uses a magnum length action.

Remington 7mm Mag is pretty flexible. You can get 100gr to 195gr Barnes in .284 caliber. Not sure if the 195gr is manufactured anymore. 139gr-175gr is common factory ammunition. To get much heavier bullets than 7mm Mag, you need to get at least a .338 Win Mag. barrel.

I am loading 120gr Nosler ballistics for varmint at 3400fps. Also can load 175gr at ~2800fps for large animals. Covers a lot of territory.

I was considering moving up to a .338 Lapua, but not sure that my Parker Hale can take it. And I think it would be cheaper to go to the new Ruger in .338 Lapua.

IMHO: Remington 700 action is accurate, but a Winchester Model 70 action is stronger.
 
Sorry for reviving such an old thread but this is a question I'm interested in. I’m trying to figure out what to do with my Winchester model 70 in 7mm mag. So are you guys saying that you can convert a 7mm mag action into a 338 Win or 375 H&H?
Thanks,
Sam
 
Unclenick's post pretty much nailed it. You can re-barrel an action for different cartridges as long as the boltface diameter and cartridge legnth remain the same.

Jim Keenan brought up a very good point though, it would probably be cheaper just to trade it in. Or as Harry suggested, keep it and buy something else. Unless you're a serious DIY'er, or you just really like that rifle, that's the route I would go.
 
You have a 7mm Rem Mag and want a hard hitting calibre ? the 7mm you have is considered on of the best all round flat shooting hard hitting calibre going, I have a heavy barrel Rem 700 in 7mm Rem Mag there is nothing down here it won't kill at long range, the 308W, 270W, or 30:06 can't compete seriously with the 7mm Rem Mag ballistics, given that all other variables are equal, I'd choose a 7mm any time.

Unless your hunting rhino or elephants (both illegal anyway) the 7mm will drop most anything on the planet to quite long distance including your bears.

I have 4 rifles which is about all I will ever need, 22, 222 Rem, 25:06 AI, and the 7mm Rem Mag, the 7mm will drop our water buffalo or wild pigs at +250m without any problems.

If the 7mm don't rock your boat, try 338 Lapua Mag or kick some serious butt with a Barret 50 BMG
 
Sam the 7mm Remington magnum is a SHORT magnum. I don't know if its action would accomodate a .375 H&H magnum.

It would, however, do fine with .300 Win Mag and .338 Win Mag. The .338 is a great round if getting kicked really hard makes you feel manly.

If you are a handloader or wildcatter, the .358 Norma and .416 Taylor will fit.
 
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