25/06 with a long chamber and recent shooting problems

Status
Not open for further replies.
lowmileage

lowmileage

Member
Joined
May 14, 2017
Messages
72
Location
NY
Long story short. I made this gun up in 1968 using a 1938 M98 Mauser action that according to NRA research at that time was a very good action. The barrel was fitted by Flaigs in Pennsylvania, a "noted" gun shop at the time. I've recently had problems with blown primers, split cases toward the rim and rounds not going off even though hit by the primer. I thought headspace and wondered why I didn't have a problem in the past. It will take a No Go and even a Field headspace gauge. Yesterday I measured the chamber using the Sinclair chamber length device. To my surprise the chamber is 2.590" long. The trim to length max for the 25/06 is 2.494" which according to what I've read means the chamber should be 2.504-2.514" long so apparently my chamber length is at best .076" to long. Could this be causing the problems I'm now having or is the headspace the problem? The funny thing is when I was using the rifle in the 70's with Hodgdon 4831 I wasn't having these problems. I'm now using IMR 4831, with adjusted loads for the differences in the powder. I was "thinking" of using resized and not trimmed .270 brass which with it's extra case length might help me out with the long chamber. I also realize shooting a rifle that will swallow a field headspace guage isn't too good an idea. Thoughts? 2506.png
 
IMO it would be best to have your barrel cut back and rechambered for proper headspacing. Also if your going through that trouble you may as well slap a spanking new barrel on it.

BTW you never posted your old H4831 load and your adjusted IMR4831 load. Maybe that info could help us with your problem
 
I put a high quality barrel on a model 700 action back in 87.I wanted a 25-06 because I had a huge amount of 30-06 brass and I wanted something good for deer and groundhogs at long range.The barrel was a prechambered #4 contour from Wilson firearms.It is one of their match grade,and they make great barrels.Nowadays,they make barrels for Cooper and Rock River Arms among others.They only sell barrels in lots of 100 or more,so I only have the one because back then,they would sell them one at a time.It wouldn't shoot less than 2 MOA.I screwed up and didn't get the headspace right,and after a couple of head separations,I went back and found out that the Field gauge was easy to close the action on.I had tinkered with it for years trying to get it to shoot,and didn't have much success.In 2014,I decided to take it all apart and start over.I put on a Holland's .250 recoil lug and trimmed the barrel shoulder in the lathe until I got it to the point that it would barely close on the Go gauge.I put it all together in an HS Precision stock and headed for the shooting bench.I shot the first shot,and it didn't blow up,so I shot again.I couldn't see where the second shot hit so I fired again.That shot made the hole from the first two shots slightly oval shaped.It's been like that ever since.I never measured the throat,but it's pretty long because I have to seat 100 grain Match Kings out a long way to get close to the lands.It actually shoots its best with about .050 bullet jump,which is a good bit.I've fitted a few barrels since then,and I have always had the best results if I stay on the tight side of the headspace spec.Very tight,as in the bolt will barely close all the way without force.Then I lap the locking lugs to get it that last tiny bit needed for the bolt to close on the Go gauge.I would imagine you need to have your headspace tightened up if you want to get the potential you want out of your gun.I don't like one to close on the No Go gauge at all,and the Field gauge,to me,says unsafe very loud if the bolt will close on it.On a hunting gun that I want the action to work slick,I lap the lugs before I do the final headspace measurement,and make it close smoothly on the Go gauge,but not on the No Go gauge.Headspace will destroy accuracy as bad if not worse than anything.Keep in mind that a tight chamber will mean you need to not let your brass exceed the maximum length spec.But,most of the time,a tight chamber won't need to be trimmed as often.Sorry for the long reply,but I can talk headspace and its relationship to accuracy all day long.
 
Here are some of the IMR4831 loads when I first noticed case seperation. The following post may include loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information. 2506.jpg
 
Last edited:
The following post may include loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.
47 grains of IMR 4831 and the 120 speer bullet gave me a blown primer on one cartridge and 2 very flattened primers on 2 others. That was with new brass, trimmed to 2.484 and annealed cases.
47 grains of IMR 4831 and the 100 Nosler BT gave me 2 rounds that were primer indented but didn't fire, another round did fire.
47 grains of RL17 and the 100 Nosler 100 BT gave me one round that was primer indented but didn't fire, one round fired ok and another round that fired and the primer slightly backed out.
52 grains of IMR 4831 and the 100 Nosler BT gave me 3 fired rounds, 1 with a blown primer and a split rim, another with a split rim indication and another that appeared OK.

Old Hodgdon 4831 loads were: 57-59 grains and the 87 grain Hornady. No split cares, no extruded primers, all rounds fired 2506 group.jpg
 
Last edited:
With that big of an overbore I would check for carbon ring, which would explain a new issue with a gun that used to shoot.
 
AJC1 said:
With that big of an overbore I would check for carbon ring, which would explain a new issue with a gun that used to shoot.
Click to expand...
I just looked up that term as I have never heard about it. I would think that my extra long chamber could contribute to that situation? But of course that doesn't answer why I can close the bolt on a No Go and Field gauge. Thanks,
 
lowmileage said:
I just looked up that term as I have never heard about it. I would think that my extra long chamber could contribute to that situation? But of course that doesn't answer why I can close the bolt on a No Go and Field gauge. Thanks,
Click to expand...
Same issue with shooting 38s in a 357 so I think a longer chamber would make the problem worse
 
Your loads don't look outrageous to me but your results from shooting scream DANGER Will Robinson. I would not continue to shoot that rifle until you get it's headspacing corrected.

Thinking outside the box here but would it be possible for your barrel to have become loose and not completely tightened down in your action?
 
Status
Not open for further replies.

Similar threads

lowmileage
  • Locked
25-06 blowing primers
2 3
Replies
56
Views
4K
Nature Boy
Nature Boy
T
  • Locked
Chamber Length
Replies
8
Views
507
murf
murf
U
  • Locked
Headspace - As It Applies To Reloading For Rifles.
Replies
18
Views
5K
Coltdriver
Coltdriver
C
  • Locked
Trim to chamber length?
Replies
10
Views
812
ctrout
C
H
  • Locked
Headspace on straight wall cartridges. What locates round in chamber?
Replies
20
Views
5K
GLOOB
G
Back
Top