Home Forums Hunting & Shooting Hunting Rifles 7mm Remington Magnum with a 22 inch Barrel

I actually read every post in this thread, which apparently some have not. (But that's usual on the Campfire. Most folks just read the OP and then respond, even if 100 posts have already thrashed over the same stuff.)

The people who have never experimented much with shorter barrels have trotted out all the old BS: that 250 fps will be lost, that the rifle will turn into a 7x57, that you'll have to use a "faster" powder to make up for the shorter barrel, etc.

None of this is true. A larger rifle cartridge ALWAYS will get more velocity than a smaller one, in any legal-length barrel. The velocity gain will also follow the same 1/4 rule, no matter the barrel length: Velocity gain will be at 1/4 the rate of powder space gain.

Also, the same powders that get the most velocity in longer barrels will get the most velocity in shorter barrels. In a 7mm RM the fastest powders will be the usual suspects: IMR7828, H4831 and H1000, RL-22 and RL-25, Ramshot Magnum, etc.

There is no way to determine how much velocity loss will be without shooting, as different loads will lose different amounts. I have seen the same barrel lose anywhere from 15 to 60 fps per inch when shortened 5 inches. The burning rate of the powder didn't matter; some faster powders lost more than some slower powders.

One general rule, however, is that the LEAST amount of velocity loss in shorter barrels is with heavier bullets and slower powders. This is counter-intuitive, and contrary to popular myth, but I have seen it over and over again in various rifles.

There have been experiments run on shorter barrels with decibel-measurement equipment and no, they are not a hell of a lot louder. What really up the decibel level is a muzzle brake or a much larger bore.--but as some perceptive person already noted on this thread, ALL big game rifles are loud. They will all make us deaf if we don't use hearing protection.

Once again the people who have actually shot shorter-barreled magnum rifles have posted good information, and those who never have posted the same old general misinformation.

I've owned several 22" barreled magnum rifles and there isn't enough difference in the ballistics to ever notice in the field--and they have all still produced "magnum" ballistics.

Banking a rigidity increase,aiding balance and making things handier...is very tough approaches to argue against,if assuming a shred of sense.

A 22" 7 Remmie makes all sorts of sense and as I've mentioned often,there's no way in hell I'd build one longer than 24" and that ain't because I've never had 'em.

Less is just so very often more....................

Exactly. I've seen increased accuracy many times with a little barrel shortening--and no, it wasn't due to the new crown, because the crown had already been "refreshed" in a search for better accuracy with the longer barrel.

As an experiment, I once shortened the barrel of a .300 Winchester Magnum to 22". Not only did it shoot better, but with published data it still got 3000 fps with 180-grain bullets. So it didn't exactly turn into a .30-06 or .308....

Thanks for the input JB.


When the road up to the range on top of the mountain thaws out enough to get up there without using a dogsled (it may be a while) I am going to get underway with load development.

Before I have the barrel cut back I am going to chronograph the loads in the 26 inch length to establish a base line so we can see how this barrel behaves when it is cut back.

I am going to concentrate the bulk of my efforts on the 162 Hornady AMax/BTSP, 160 Speer, and a yet to be determined 175 of some kind.

I'll be interested in hearing the results!

i've a Win. Laredo 7mm Rm donor, a Brownell's muzzle crowning tool set, and a Sawzall. probably too late to get the rifle back from Aronold at CS to hack up...

i'm sure the cut/chrono/repeat to 16" game has been done before though.

Yeah, a number of times. The results always vary somewhat more than the theoretical amount supposed by humans or computers.

In fact some experiments have shown an occasional increase in velocity when a couple inches of barrel have been sawn off--probably due to sawing off a slightly loose spot in the barrel.

I once shot 4 loads (2 factory and 2 handloads) from a pair of 9.3x62's, one with a 23.6" barrel and the other with a 20.5' barrel. Only one load lost as much as 80 fps, two were very similar, and one load even gained velocity slightly in the shorter barrel.

That goes both ways JB.

Ken Waters reported that he gained around 100fps when he went from 22" to 24" with the .270 WCF. He also mentioned a letter from JOC who reported the exact same increase.
My own experience with the .270 WCF also showed a 100+ fps increase when stepping up to a 24" barrel.

As I noted above in one post, I once saw the same barrel vary anywhere from 15 to 60 fps PER INCH with different loads. Which means two inches of barrel could gain or lose 120 fps. And that was a 7x57.

I once tested a 26" barreled .270. With the more-or-less standard load of 60 grains of H4831 and a 130-grain bullet, it got anywhere from 3250 to 3330 fps, depending on the bullet. But as I also noted earlier, the least amount of velocity loss (or gain) will be with heavy-for-caliber bullets and slower powders.

From past experience, I would guess a 22" barreled will get an easy 3050 with 160's and 2850 or so with 175's, the bullet weights HBB plans to use. And no .280 will get those sorts of velocities from a 22" barrel.

................JB...........Very well stated.

There are many mis-conceptions and mis-information about the shorter barrels, which in some cases, is usually offered by those who have little to no experience with them. The extra noise factor along with the more muzzle blast from the shorter barrels, are imo, over exaggerated. And, when the OP wishes to have a 7mm Rem Mag rifle chambered in a rifle with "ONLY" a 22" barrel, here come the usual comments just as you say above, such as;,,,"might as well just get a 280 Rem or some other std 7mm cartridge.",,,,,,"a shorter barreled 7 mag is just a big waste,",,,,,,,,"you`re gonna lose ALOT of velocity,",,,,,,or,,,,,"if a 22" barreled 7 mag were proper, then why don`t the rifle makers chamber the 7 Rem Mag in 22" rifles?"........La de da de da...And the mis-information and mis-conceptions go on and on.

I`ve taken alot of heat on this forum in the past for owning a 16.5" barreled 300 WSM Ruger compact. I think I`m the only one on this forum that owns one, which is well and fine with me. Some have stated; paraphrasing,,,,"I should have just bought a 24" barreled 308 or a 30-06."..."That rifle won`t live up to the full potential of the longer barreled 300 WSMs."..."I`d never own a 30 cal magnum in such a shorty tube."...."Short tubes defeat the purpose of a magnum."..."You`re losing a bunch of velocity"...."Lose your hearing yet?"..."That damn thing must be soooooo loud."..."What did you say?"..."I can`t hear ya."..."The muzzle blast on that thing must be really bad.".."Wouldn`t want to around that thing when it goes off."....And the list goes on and on.

The truth is, is that none of these past and present nay-sayers have ever owned nor chronographed a 16.5" barreled 300 WSM Ruger compact, let alone own a 22" barreled 7 Rem Mag (the subject of this thread). Yet when subjects like this one come around, they then become the "so-called" short barreled experts, posting their usual beefs, mis-information and mis-conceptions regarding short barrels, whom to begin with, would never own a shorter tubed rifle chambered in a magnum round.

Magnum rounds from shorter tubes are very taboo to most. But generally from this same crowd, the 45/70 carbines with 18.5" tubes seem fine. 21.5" tubed 375 H&Hs from the Sako Kodiaks are ok. 20" tubed 375 Rugers seem ok. 20" tubed 300 and 338 RCMs are ok.

But when it comes to 7mm Rem mags, 300 WSMs, 300 and 338 Wins and other similar magnum rounds from shorter barrels? "Throw them under the bus."..."Melt them suckers down."...."What a big waste",,,and more blah blah blah.

Again, very well stated JB.

I had one 7RM cut down from 26" to 24", and lost 50-60fps with the same loads. Barrel lengths of 21.5" to 25" suit me fine on my rifles unless its a rimfire - then 20" or under is fine.

MtnHtr

IDK about a 22-in. 7RM, but I sure wish I'd gotten a Remington 700 African Plains Rifle in .270 WCF about 20 years ago. If I ever wear out my Mountain Rifle bought at a yard sale summer '88, I might have to go long.

The idea of a 130 going 3,300 or more makes me giddy. Reckon one could break 4K with an 85 TSX?

Hotcha!

For fast and wicked look at the .257 Roy and 80 or 85 grain bullets. They make things go splat

A good crown,often works WONDERS...................

I almost forgot. How much weight do you figure cutting four inches of barrel off will net? 5-6 ounces?

Yep, my program showed 4.8 oz based on .650" OD and .284" ID and 4" length.

Here's a great program for weight calculations.

http://www.matweb.com/tools/weightcalculator.aspx

Thanks for the length/weight calculator link. That is a handy gizmo.

hillbilly,

How about make an experiment of it and chop off and crown an inch at a time and post the average velocity changes. Use a standard bread and butter load and lets see what actually happens. Speculation thrown out the window, I'd like to see some actual numbers as barrel loses bore volume.

Good Luck!

I'll see if it can be practically done 1 inch at a time when I get underway.

HBB, if you do choose to undertake this experiment you can of course skip the crowning and still get good velocity loss data.

May save some money too if you're not crowning them yourself.