What to Do….M70 SS Action

Gomer

Gomer

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I picked up an M70 Classic Stainless in 300 Win Mag from a local pawn shop for $475. I went over every bit of it to find out why it was so cheap, but it appears to be in good condition. It has one of those BOSS thingers on it. My first instinct was to remove it and put a thread cap on it, but the threaded portion is quite a bit longer than normal. If I cut the threaded portion off, the barrel will be about 22 3/4” long. Seems kinda short for a 300.

Thinking of rebarreling it. I already have a different 300 Win Mag, so maybe considering 338 Win Mag (I do have a 375 Ruger) or maybe a 257 Weatherby. If I leave it as a 300, I would probably load it with something heavy and use it for heavier cover/shorter shots. My other 300 has a 26” barrel and shoots 168gr TTSX really well at nearly 3300 fps. So, it’s the same cartridge but two really different setups.

As it sits, my 3.34” magnums are a 7mm Rem Mag, 300 Win Mag, and 375 Ruger.
 
The BOSS system was actually an add on option. It works very well in fine tuning accuracy by playing with the barrel harmonics. They only discontinued it because it violated Browning's patent. Why wouldn't you want to use it?
 
migrabill said:
The BOSS system was actually a rather pricey add on option. It works very well in fine tuning accuracy by playing with the barrel harmonics. Why wouldn't you want to use it?
Click to expand...

I hate muzzle brakes. To me, it just looks goofy. It has both ported and non ported BOSS dinguses. I think the threads are worthless for anything other than the BOSS.
 
Gomer said:
I picked up an M70 Classic Stainless in 300 Win Mag from a local pawn shop for $475. I went over every bit of it to find out why it was so cheap, but it appears to be in good condition. It has one of those BOSS thingers on it. My first instinct was to remove it and put a thread cap on it, but the threaded portion is quite a bit longer than normal. If I cut the threaded portion off, the barrel will be about 22 3/4” long. Seems kinda short for a 300.

Thinking of rebarreling it. I already have a different 300 Win Mag, so maybe considering 338 Win Mag (I do have a 375 Ruger) or maybe a 257 Weatherby. If I leave it as a 300, I would probably load it with something heavy and use it for heavier cover/shorter shots. My other 300 has a 26” barrel and shoots 168gr TTSX really well at nearly 3300 fps. So, it’s the same cartridge but two really different setups.

As it sits, my 3.34” magnums are a 7mm Rem Mag, 300 Win Mag, and 375 Ruger.
Click to expand...
358 Norma mag and have a great all weather thumper for North America!
 
Rebarrel it to 338 win mag

Or..... leave it a .300 win mag and cut it down to minimum length and screw a nomad LTiXC on the end of it. That would be a super cool rifle. Just dont shoot it without the can on it!
 
I have a 338 win mag just like that one .You can go on ebay and get the cr none ported boss for it .My 338 is accurate 3/4 inch at 200 yards with factory ammo .It kicks like a 270 with the break on snd like a mule with it off .They are very accurate when you tune them in just shoot it .
 
dgr416 said:
I have a 338 win mag just like that one .You can go on ebay and get the cr none ported boss for it .My 338 is accurate 3/4 inch at 200 yards with factory ammo .It kicks like a 270 with the break on snd like a mule with it off .They are very accurate when you tune them in just shoot it .
Click to expand...

Luckily, this rifle has both versions of the BOSS. I will mess with them a little before doing anything real drastic.
 
I can tell you that someone makes a thread protector for those 9/16-24 threads, as I picked up a similar 30-06 years back and it has the thread protector on it. I love that rifle. I was not sure how it would shoot with such a short barrel, but with the same ammo it clocks within 50 fps of my other 06's with barrels 2-4 inches longer. Don't know why or how, but it does.

1788827821537.png
 
22" is perfect on a 300win, I have a custom built one with 22" barrel and the velocity is same as my old 26" custom gun.
I shoot a 200gr Accubond at 2850fps.
 
You should sell it to me for what you paid.....And I will build a 416 Taylor !! :E Rofl:
 
Choupique said:
Because itll shoot really good and wreck all of your plans.

Nope. Dont do it. When you buy a donor the FIRST thing you do is unscrew the barrel.
Click to expand...
Ive shot my donor rifle. But no worries, Im still going thru with my build plan.
 
Some years back I had a Donnelly barrel and needed an action for it. I bought two rifles (one at a time) with the intent to use the actions for the barrel. Both rifles were so nice they got left as is and I finally solved it by buying a a stand alone action.
 
Shoot it you will be suprised Ebay has those nonported convential recoil add ons .My 338 with a boss model 70 outshot my cousins $5000 custom rifle made in 1998 by far .A 3/4 inch group with factory ammo and standing postition from the bench off a bull bag and milk crate with the boss winchester .My best friend in Alaska borrowed that rifle shot 7 moose dead in their tracks from 25 to 350 yards .He also shot a 7.5 foot grizzly with it .The only thing that rifle needs is a better trigger and maybe better stock but that plastic stock went through hell in Alaska plus a nikon monarch 3.5x10 x50 scope .I had switched to 338-378 weatherby .I would use 200 gr partitions or accubinds in that rifle and see how accurate it is .I wouldnt believe 3/4 inch groups at 200 yards with that straw barrel .My 338 win mag kicks like a 270 and its super light .I put the cr boss on to hunt with .
 
dgr416 said:
Shoot it you will be suprised Ebay has those nonported convential recoil add ons .My 338 with a boss model 70 outshot my cousins $5000 custom rifle made in 1998 by far .A 3/4 inch group with factory ammo and standing postition from the bench off a bull bag and milk crate with the boss winchester .My best friend in Alaska borrowed that rifle shot 7 moose dead in their tracks from 25 to 350 yards .He also shot a 7.5 foot grizzly with it .The only thing that rifle needs is a better trigger and maybe better stock but that plastic stock went through hell in Alaska plus a nikon monarch 3.5x10 x50 scope .I had switched to 338-378 weatherby .I would use 200 gr partitions or accubinds in that rifle and see how accurate it is .I wouldnt believe 3/4 inch groups at 200 yards with that straw barrel .My 338 win mag kicks like a 270 and its super light .I put the cr boss on to hunt with .
Click to expand...

I have a few options. The rifles comes with both BOSS thingers, the ported and the non ported. I also found a company that makes a thread adapter specifically for the BOSS threads, so I ordered one of those.
 
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