Home Forums Hunting & Shooting Hunting Rifles 7mm Practical, anyone?

Reaming one out....

Better thinking would be to cut off a neck length of barrel shank and then a re chamber. Reamer dia vs old chamber dia could be a miss fit, not to mention if the factory barrel is not machined with bore and chamber aligned. There will always be some run out, how much is a question. The gunsmith will need some latitude in cleaning up bore alignment with chamber mis alignment with the new chamber. This can be more work than chambering a new barrel.

Also, don't expect any accuracy guarantee.

Fotus, excessive freebore and throat dia allows a lot of gas blow by resulting in velocity loss, not to mention bore dia varies...reamers and throat geometry count.

I shoot a 7 STW with a Pac Nor 27" tube, 140g tipped tripple shock at 3650, tiny groups...550 is a chip shot. Barrel is twisted for 140-150g Noslers with 3750 fps being a max load with accuracy for the 140g C/T bullet. Obviously, I don't shoot long range, just do not like running deer. Same load with a 140g Nosler C/T bullet has never failed brother and I also....never on BIG Kansas deer that go over 300 lbs out to 550 yards. Kansas record white tails run over 400 lbs...we have not seen any of these.

Since good Winchester brass has disappeared for the 7 STW, I have designed a 7 Mashburn reamer and a 7 Practical That I hope to chamber this year in Brux barrels for use in Old blue bag winchester brass. I did not design a CIP spec reamer for RWS brass.

The 7mm Practical was what sent me in the direction of my 7.21 Sage. My version of the 7-300. Mine has minimum case taper and a 35 degree shoulder.

Shoots a solid 1/2 MOA or better. I’ve only shot three shot groups seeing it’s a magnum I use for hunting. Also from past experience it won’t be easy on throats. So I don’t heat it up. It’s a 8 twist, 3 contour Schneider Barrel. Took my first game with it this last fall season. Two Mule deer, one at a bit over 400 and one at 847. Both were Bang Flops with the Hornady 180gr ELD-M @ 3183 FPS.

Shoots the 162gr ELD-X well.

300yards 3325 FPS / This was my top end. I backed it down a bit.



300 yards@ 3256 FPS. My fireforming loads shot extremely well & fast.



300 yards



180gr ELD 300 yards @ 3183 FPS

7.21 Sage cartridge (Left)
.338 Winchester Magnum case (Center)
On the right is a .300 Win Mag case with a .338 230gr ELD-X, when fire formed it will have the same 35 degree shoulder and case taper as the 7.21 Sage on the Left.

Out of complete curiosity and due to my addiction to tinkering and wildcat chambering. I decided to do the exact same 7.21 Sage concept but necked up to .338. Grant at JGS said my reamer should ship next week. I already have a factory Rem700 .338 Ultra and a Benchmark built .338 Edge (Which is spooky accurate) but I wanted to see if I could get similar gains as I did with the 7.21 Sage over the 7mm Magnum using the 300 Win mag case.

7.21 Sage cartridge (Left)
.338 Winchester Magnum case (Center)
On the right is a .300 Win Mag case with a .338 230gr ELD-X, when fire formed it will have the same 35 degree shoulder and case taper as the 7.21 Sage on the Left.

I’m looking forward to load development.

Pass the 7-08,the 180 ELD and hold the Fluff.

Hint..............

In this day and age, I don’t know why one would choose a belted case for a wildcat when there are belt-less alternatives available.

REDUX

"Don't Worry, Be Happy"

Jerry

I’d like to see the results. What barrel length are you going to put that in?

I’d like to see the results. What barrel length are you going to put that in?

(5) rounds in the belly,killer brass abounds,barrels live forver and 2600fps is a breeze in a rather modest spout(21"). In my current atmosphere,it is supersonic to the 1765yd line.

Hint................