16" Barrel 7mm

[picone]

I'm new to hunting, but not short of opinions on my gear.

I want the shortest, ligthest rifle I can practically have...but I still want some serious knock-down power.

I'm pretty sure 16" is the shortest practical barrel length for this project (but I wouldn't be opposed to going shorter). I'm looking at ballistics and estimated velocity loss in a 7wsm, if I cut it down to 16". I've looked at 270cal as well, but it looks like 7mm would be slightly more optimum for heavier bullets and energy. I'm well aware that I'll be losing quite a bit of velocity cutting the barrel this short, but 300fps on a 3-400yd hunting shot seems reasonable for large animals. A 270wsm seems like it would have ballistics of a 270win, and a 7wsm, a 7-08. Anything I intend to hunt would be adequately taken down with a 270win (provided I do my job).

Am I missing some vital information/understanding on this project? Any reason to think I would want to twist faster (I would think not, but...). 1:9 is on the faster side for 7mm. Any bullet stability issues I should expect knowing the powder efficiency would be dismal? I'm thinking my load build up would definitely lean towards the faster powders on the charts.

Any insight and/or criticism would be greatly appreciated before I just do it and figure it out.

Thanks,
Dom

 

[Hydenseek]

Interested in answer here. I have the same beliefs as you. I believe accuracy trumps the speed difference.

 

[Outrider27]

Don't forget that if you go shorter than 16" you will have to do some serious negotiating with the BATFE and fork over $200 for a tax stamp when the paperwork is done and submitted (about 6 months process right now), as you will be creating an NFA Class II device. And that's if your local sheriff (or whoever is the chief law enforcement officer in your county) will even sign off on the Form 4.

Personally, I wouldn't push it that close to the limit - 17" or 18" is short enough, since velocity loss isn't an issue that worries you. To get an idea of size and weight, you might see if anyone in your area has a Remington 600 or 660 you can look at and handle; they have 18.5 inch barrels. Muzzle blast will be a bit of an issue with magnum cartridges; my 600 in .308 Win isn't too bad in that respect, but 600s in 6.5 and .350 Rem Mag had a well deserved reputation for notable muzzle blast.

 

[AckleymanII]

Don't forget, those ultra light rifles can kick the fillings out of your teeth also! So, how much recoil can you handle and still shoot accurately? Everyone is different!

 

[rickiesrevenge]

I bet you loose right at 250-300fps from what a normal barreled rifle gets. What weight bullets are you planning on shooting? I've got a couple big 7mm's with shorter barrels. Both are XP-100 pistols. They are chambered in 7mm Dakota. Yes they are loud. One has a 17" barrel and the other 20". I get 2775 out of the 17" and 2825 out of the 20" with bergers 180 Hybrid.

 

[OIF/OEF]

Subscribing I am interested as well I think the idea is cool get a tank style muzzle brake and let me know how violent it is. Cool project.

Cut it down to 14 inches and 'pin" a 3 inch muzzle break on it......it that legal?

 

[picone]

Don't forget that if you go shorter than 16" you will have to do some serious negotiating with the BATFE and fork over $200 for a tax stamp

10-4. I'm in CA. Remembered it (incorrectly) as OAL, not barrel length. I'd be happy w/16".

 

[picone]

Don't forget, those ultra light rifles can kick the fillings out of your teeth also! So, how much recoil can you handle and still shoot accurately? Everyone is different!

Hopefully only have to do one, right?

 

[picone]

I bet you loose right at 250-300fps from what a normal barreled rifle gets. What weight bullets are you planning on shooting? I've got a couple big 7mm's with shorter barrels. Both are XP-100 pistols. They are chambered in 7mm Dakota. Yes they are loud. One has a 17" barrel and the other 20". I get 2775 out of the 17" and 2825 out of the 20" with bergers 180 Hybrid.

150gr, most likely. I would try 160gr, and even 165. I want it to stay as flat as possible...which is why I was leaning towards the 270. I've convinced myself the 7mm is a better choice. We have to do "lead free" out here and selections are pretty limited...especially when you try to find ammo the week you're going hunting.

 

[picone]

Subscribing I am interested as well I think the idea is cool get a tank style muzzle brake and let me know how violent it is. Cool project.

Cut it down to 14 inches and 'pin" a 3 inch muzzle break on it......it that legal?

Muzzle break would be nice, but not necessary. Depends if I can find something low-profile so it doesn't snag twigs and stick them in the barrel, and deffinitely has to be easy to clean. Vais would be nice, but i would have to bring something special to clean it out, just in case. If it kicks really bad (which I'm guessing it will), it just won't get shot much. It will be the one I pull out for my buddy and say "Oh try this little short one".

My latest hunting experience had me hiking down some really rough hillside going straight thru thick brush and hog beds, in the rain, for hundreds of yards. 24" rifle barrel was just a PITA. So was the 56mm scope, but that's another topic.

 

[fredo]

As your hunting experience progresses, you'll be learning that "shortest" or "lightest" doesn't equate to being the "best-est" in a rifle.
Everything is a compromise. From barrel length, to cartridge capacity, to bullet choice, to ballistics, to overall weight...they all affect how your rifle will handle, shoot and perform on game.

If I were building a hunting rifle to accentuate "short & light", it'd be chambered in 7-08.
Push a 120gr TSX crowding 3K from a 18-20" light contour barrel. Recoil would be marginally snappy in a 6-7lb. rifle, but not punishing or harsh at all. And it'll shoot plenty flat for normal hunting distances. That 120gr TSX is "lead free", and there ain't no ungulate in North America that it won't blow a hole thru at reasonable distance...

Drop your shorty in an AWR stock, top it with a Leupy VXIII 2.5-8x36 sittin' in Talleys.

If you feel you must, go 16". But I'd err on legality and stay 18", minimum. On a light contour barrel, that translates to only a few ounces, and it'll carry plenty small. Either way, your bell is gonna get rung when ya pull the trigger on that shorty sumbeach.

You're welcome...

 

[Outrider27]

Cut it down to 14 inches and 'pin" a 3 inch muzzle break on it......it that legal?

You're treading on thin ice there, and can, on any given day, get conflicting answers from the BATFE with regard to whether pinning is permanent and thus constitutes a 16" barrel, which means a big fine and/or prison if you get the wrong inspector. Best bet is to not even THINK about going there; consider 16.5" the absolute minimum. From a weight and handiness standpoint, I've found 18"- 18.5" to be fine.

If it were me, I'd start out at 18.5" and work from there; if you find it absolutely has to be a bit shorter, it can always be shortened a half inch or an inch at a time and re-crowned. You can always take more off, but you can't replace what isn't there, plus starting at 18.5" has the potential to minimize velocity losses even if you end up taking a bit more off.

I have a BATFE Class II short barrel (8.5") rifle with a suppressor (2nd $200 tax stamp : ) that puts it up around 16", and frankly it isn't any handier than my Rem 600 at 18.5". But it does look a bunch more evil than the 600...

 

[MrMajestic]

 

[Outrider27]

Lol; that photo is doubly humorous to me MrMajestic. I used to shoot a 30-30 14" Contender in IHMSA unlimited class and hit upon an H380 load that was an absolute tack driver for accuracy. It didn't have a fierce muzzle blast noise wise, but the flash was spectacular...

H380 doesn't seem like a great choice for a 30-30 pistol with a 14" barrel, but a lady named Josie Engle had already set a national record with one using a similar load and I had some lying around, so I tried it. After the accuracy it delivered, like the OP, I wasn't worried about the velocity, just being careful not to set the grass on fire at late summer matches.

 

[shoot4fun]

In my experience with the 7WSM, I would say it has a lot more going for it than it gets credit for. Superbly accurate and versatile to boot. It can hurl bullets from just over 100 to 180 grain easily. My 180 VLDs were zipping out of the 26" barrel at 2980 FPS and had great 1000 yard accuracy and energy.
I feel like you will lose more than 300-400 FPS because you really need slow burning powder to get case volume in the WSM. Also, for all the trade-offs, I would recommend chambering in 7MM-08. Love mine for hunting and the little Model 7 is just the perfect light, short and handy rifle for it.

 

[mac86951]

Completely hypothetical as I don't know your load, but:

For Example Purposes only:
Quickload with a 26" barrel
Base Loading: 160 Sirra SPBT #1920, 65gr IMR 7828SSC
muzzle velocity of 3005fps

same load in 16" barrel:
muzzle velocity of 2603fps

That would give us a reduction of 400fps, or 40fps per inch of reduction from 26"

This calc is going to have some error, as the slow powder wasn't fully burt to begin with.

Same calc with same bullet using alliant reloader 19 (58gr)
26" muzzle velocity 2920
16" muzzle velocity 2552

or a change of ~36fps per inch of barrel length loss below 26"

Conclusion:

Can you do it? Yes. I'd stick to lighter bullets and faster burning powder, but you will lose from in the neighborhood of 30-40fps per inch under 26"

-Mac

 

[picone]

I'm in agreement with you on leaning toward faster powder and lighter bullets. May I ask if and what program you are using for those numbers? Also, most published numbers for all wsm's are in 24 and 22" barrels.

 

[mac86951]

Quickload. I would guess same losses along range of 26-16" barrels, so take my listed velocity (near max) for 7wsm, and subtract 80 for 24", or 160 for the 22" barrel. I'm easily off by 10-15 fps so this is in no way an alternative for actual shooting, but it might get you pointed at the right barrel length

 

[fredo]

My 7WSM has a 24" barrel, and I wouldn't want it any shorter. Getting all you can out of 180s means you'll need to single feed a SA, or build on a long action. The former is not acceptable for a hunting rifle, and the latter goes against the notion of weight savings. I shoot 162Amaxs from my SA...

My 7-08 is on a Model Seven, w/ 23" Broughton #3 contour. Under 8 lbs loaded & sling, balances perfectly and throws a 120TSX @ 3125 with a full case of Varget. I use Lapua .308 brass, necked down, and the 120s feed smoothly from the short Seven action...

Having both, I'll reiterate opting for the 7-08 for a short barreled hunting rifle. And when considering that the availability of 7WSM has been in a state of "unobtanium" for a few years, the 7-08 makes all the more sense.

Whatever you decide, good luck & have fun!