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Thread: M70 Quandry

  1. #1
    Member Darreld Walton's Avatar
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    Default M70 Quandry

    I picked up an M70 Winchester .375 Safari Express, one of the push feed jobs with the barrel mounted recoil lug. The metal still bears original finish, and virtually no wear, but the previous owner used an aftermarket 'glass stock, and bedded another 2-2 1/2 pounds of shot into the forend, bringing total weight up around 12 pounds sans scope.
    Without the 'right' stock, this thing is a shooter, but about useless at this weight and length. Has anyone actually put one of the shorter barreled .375's across the chronograph with useful loads to see how much velocity is actually ending up as flash at the end of the tube? I've been thinking of leaving this one at the original diameter, but cutting it back to 20 inches, having it bead blasted and parkerized, and putting it into a straight combed, 'classic' or 'express' style laminate, and using iron sights. (Yes, the black timber does get a little claustrophobia-inducing tight down here once in awhile).
    What would you do? Leave it as is and use the bejeebers out of it, or try and make it a bit more useful?

  2. #2

    Default M70 Quandry

    Darreld, I would get rid of that stock, 12 1/2 lbs is to much weight to be lugging around!!! If you cut the barrel back to 20 inches, you will lose 50-100 ft per inch cut off. There are many 20" 375 H&H's out there tho, & if I had that gun, the stock would definately go. You can probably pick up a Boyds Laminated stock for about $100 and they are 99% finished. Or a variety of synthetic stocks can be had. I used a 375 H&H as my everything gun when I lived up there, I had a Rem 700 rebarreled to 375 H&H and a Brown Precision fiberglass stock put on, it shot great and with scope it was right at 8 lbs.

  3. #3
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    Default short-barreled 375

    I had a Rem 700 Classic 375 shortened to 21", including a muzzle brake, so my barrel is actually only 19.75" or so. I chronagraphed it after having the work done on it and it shot 57 fps slower than Rem's published speeds(w/24" barrel). I was shooting 270 grn factory Core-Locks. I'm very happy with it, and if anything it is more accurate with the shorter, stiffer barrel. Mine's kind of light (standard contour barrel), that's the reason I went with the brake. Nothing fancy, but works good.

  4. #4
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    Default

    With the expansion ratio of a 375 caliber firearm you will not lose 50-100 FPS per inch cut off. You will more than likely not even lose 100 FPS from the original 24" barrel if you go to a 20" barrel. I have a Sako AV in 375 H&H with a factory barrel of only 20". Although I have never chronographed it, I'd bet good money that it is not losing 100 FPS from a 24" barrel.

  5. #5
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    Default Short barrels & velocity...

    When shortening the barrel on a rifle the velocity loss is dependant on several factors. The biggest, as Allen says is expansion ration. The bigger the bore the less the velocity loss per inch. In other words a 375 will suffer less than a 338. The 458 will have less loss(!#*) per inch than the 375. I've owned two 20" barreled 375's, both Sako's and they had almost identical velocity with all bullets. With 300 grain Nosler partitions , the 20" guns were 2447 fps as compared to a 22.5" with 2530 fps and the 24 3/8" barrel at 2573 fps, when loaded with 78.0 grains of H4350. When loaded with 70.0 grains of RL-15, the same bullet was 2567 fps from the 24 3/8", 2545 fps from the 22.5" and 2467 from the 20" barrel. This was expected and and typical of RL-15 vs H4350. RL-15 does better in short barrels. It is also quieter (less muzzle flash) and gives more consistant velocities. Twenty one inches would be a very good compromise with this powder.

    Now these were all different rifles with different internal dimensions and different barrels, your mileage may vary, but this is typical performance. I did not cut the barrel of one rifle. A 20" barrel on a 375 or even a 338 Mag is not too bad, just a little noisy. A 270 or a 7 Mag seems to loose a lot in a loss of four inches of barrel.

    A 375, 300 grain at 2450 fps, will do everything inside 200 yards that it will at 2550 fps. The difference will require the shooter to account for the arc of the trajectory. Not a big deal. The 376 Steyr round is a great performer in short barrels. It gets really close to the old H&H when both barrels are short. Good shootin'.

    Murphy

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