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modifying a-bolt mag to permit greater oal

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20 August 2006, 01:57
molar1
modifying a-bolt mag to permit greater oal
The detachable magazine on my a-bolt 300 win mag will only permit bullets to be seated to 3.340" . I need to seat the bullets to 3.490" to be .010" off the lands. I have heard some people say that you can file away some metal at the front of the mag to overcome this issue, but I am concerned this will weaken the mag. Others have suggested that a 375 H&H magazine will work as well. Anyone tried either of the two methods?
20 August 2006, 02:58
Strut10
If the H&H mag will feed, it'll give you plenty of clearance. You can go from 3.585" - 3.6" (yep......they're not all the same) with it.


Founder....the OTPG
20 August 2006, 06:24
fredj338
molar, this or that distance from the lands is not magic. Just work up a load that shoots well w/ your mag as is. bewildered


LIFE IS NOT A SPECTATOR'S SPORT!
20 August 2006, 07:35
molar1
Normally I would do just that. However, I am using a nosler partition 180 gr spitzer which nosler says must be loaded longer than 3.340" else the bullet might fall into the case during recoil (because the bullet is seated past the end of the ogive curve). I know they make the protected point just for this, but this bullet has a much lower bc than the spitzer(this is a big deal to me). Hence I need to find a way to seat the spitzer out a little farther.
20 August 2006, 08:47
jeffeosso
the mag is either very thick on the front or has a "plug" as a spacer there.. at least that's what they do with 708s adn 270s... and you have to modify them... i don't recall that the abolt was made any longer...

Not that it matters, but my starting point is .027 to .0300 off, but with your 3.490 startying lenth, and additional 20thou isn't going to help.

I don't suggest a hunting rifle close to the lands, but that's just me

jeffe


opinions vary band of bubbas and STC hunting Club

Information on Ammoguide about
the416AR, 458AR, 470AR, 500AR
What is an AR round? Case Drawings 416-458-470AR and 500AR.
476AR,
http://www.weaponsmith.com
26 August 2006, 08:36
Rancho Loco
The .375 H&H is the way to go..

That's what I have in my .300 WM A-Bolt.
26 August 2006, 09:06
bowhuntrrl
quote:
Originally posted by Rancho Loco:
The .375 H&H is the way to go..

That's what I have in my .300 WM A-Bolt.


Ditto on that !!


Elite Archery and High Country dealer.
27 August 2006, 09:17
molar1
Does the 375 mag fit the gun without modifications?
28 August 2006, 17:58
Reloader
I pose this question for Model 70s as well as just like the A-Bolt the 70s have very short clip lengths. I just hate loading for Brownings or 70s because of this. Anyone have any good suggestions for the 70s as well?

Right now I am doing load developement on a newer model 70 and I'm having to load around 1/4" from the lands!! Reminds me of Weatherby's free-bore Roll Eyes.

I have loaded for several Wins and Brownings that shot reasonably well despite this problem. I do feel they could be better if they didn't have Lawyer clips Big Grin.

Reloader
29 August 2006, 03:37
MTM
Mod. 70 Classics you just take out the spacer, adjust the ejector and bolt stop.