Gunsmithing My rifle shoots like a shotgun!

[Pogo57]

Surplus Mauser action build up in 6.5x55 Swede. Barrel is a Adams and Bennett 21" and very, very light. Glass bedded. Free floated. Tubb's Final Finish kit. Approximately 300rds total.

My goal was to have a very light, handy deer and elk rifle and sometimes it is. I expected that the barrel would heat up pretty quickly being so light. I figured if I could get 1 1/2" 3-shot groups at 100yds, I'd be ok with it.

Have tried various loads with several powders and bullets and occasionally get a sub-inch group. However if the barrel gets at all warm (can still hold it but warm after 3 close together shots), it starts shooting like a shotgun! Groups will open up to 6" or even 8"!

While I realize that this is NOT a precision build, isn't this worse than I should expect? What can be done, if anything?

 

[tfsron]

Re: My rifle shoots like a shotgun!


You can try putting a pressure point on the barrel at the forearm.
Shim with hard paper until you get the best groups, then glass in the same thickness.
10 to 15 Lbs. pressure on the barrel seems to help light barrels.

If a pressure point does not help, there are one or more problems in the rifle you will have to find and fix.

Good luck
Ron

 

[xs hedspace]

Re: My rifle shoots like a shotgun!

+1 on the pressure point idea. But a hunting rifle only needs the first 2 or 3 in the right place, unless a herd of buffalo is charging, right? 6.5x55 not good for charging buff anyway. You could try sending the barrel to a cryo stress relieving company, since the heat is probably warping the tube slightly, but the pressure point idea should be enough for a hunting rifle. Sight in with 3 shot groups, not 5.

 

[Greg Langelius *]

Re: My rifle shoots like a shotgun!

+10/both comments.

 

[Keith Johns]

Re: My rifle shoots like a shotgun!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: xs hedspace</div><div class="ubbcode-body">But a hunting rifle only needs the first 2 or 3 in the right place, unless a herd of buffalo is charging, right?</div></div>

Sorry but I STRONGLY disagree with that.


If it's shooting 8MOA there's something wrong with the rifle. Even with a noodle barrel, that's absolutely terrible.
Send it back to whomever made it. He may be calling the barrel maker for a new tube.


I'm assuming very little human error on the part of the shooter

 

[BLAWTON]

Re: My rifle shoots like a shotgun!

I you want to get the stress out try harmonic stress relief. It is alot more effective then cryo. PM me if you want more details.

 

[wnroscoe]

Re: My rifle shoots like a shotgun!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pogo57</div><div class="ubbcode-body">Surplus Mauser & Adams and Bennett Barrel </div></div>

Even this combo should shoot better than 8" at 100 yards.

The metal work and barrel would be suspect at this point.

 

[Lumpy Grits]

Re: My rifle shoots like a shotgun!

Have you had a anyone else shoot it yet? Try that, and see IF it's the same or not.
Respectfully,
LG

 

[bohem]

Re: My rifle shoots like a shotgun!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wnroscoe</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pogo57</div><div class="ubbcode-body">Surplus Mauser & Adams and Bennett Barrel </div></div>

Even this combo should shoot better than 8" at 100 yards.

The metal work and barrel would be suspect at this point. </div></div>


I agree, they're not the best, but I've done quite well with that combination assuming proper care is given to the chip mmaking

I have this combo with a heavier barrel and it shoots sub MOA to 600 without much issue.

 

[Pat M]

Re: My rifle shoots like a shotgun!

? scope ?

 

[chpprguy]

Re: My rifle shoots like a shotgun!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pat M</div><div class="ubbcode-body">? scope ? </div></div>

+1, mounts, etc? good scope?

 

[bohem]

Re: My rifle shoots like a shotgun!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chpprguy</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pat M</div><div class="ubbcode-body">? scope ? </div></div>

+1, mounts, etc? good scope?

If you have an oven, you can try normalizing the barreled action.... </div></div>

This is a bad idea.

If you manage to get your oven hot enough to Normalize Steel (800+*) you have no control over the cooling rate and almost no control over the actual temperature that the oven is sitting at. A normalizing process requires a steady temp within +/-5* to be consistent.

It's not an issue of heat treatment. I suspect the metal work WAY before I would suspect a HT issue.

Try the barrel block pressure point and then check for issues in how it was machined.

If it's just a prethreaded barrel that was spun into the action and checked for headspace you should make sure that the barrel is tight and also that it's aligned right.

 

[NOMISS]

Re: My rifle shoots like a shotgun!

Although the rifle is bedded check and see if there is play between the recoil lug and its bearing surface - there should be NONE, check your float between the forend and barrel, with such a light barrel it might be 'flipping' (hitting) off the barrel channel as the bullet moves down the barrel, so maybe increase the space between the barrel channel and barrel right up to where the barrel meets the reciever, also dont 'drag' out of the action screws when tightening up, use a torque limiting action wrench, using Loktite and about 3-5 foot pounds pressure.
Hope everything works out.

 

[Halfnutz]

Re: My rifle shoots like a shotgun!

I just saw a surplus Mauser w/ "chicken hawk" proofmarks made in 1944 last week at a local smith's. He was asked to rebarrel it to .308. The smith warned the customer that the reciever may be Brittle or soft as it was possible that it had been produced by slave labor. The customer agreed and had the smith do the job. After barreling and checking headspace the gunsmith fired three rounds. First round was OK. Second round,slightly stiff bolt lift and primer begining to flatten. Third round, stiff bolt lift and primer completly flattened. He then rechecked the headspace and the NO-GO dropped in. After removing the barrel there are shinny spots where the lugs contact. He will not reinstall the barrel.

According to him it is said that anything after 1942 can be suspect. I am not trying to be an alarmist but would suggest you look into it's history as a precaution.

 

[chpprguy]

Re: My rifle shoots like a shotgun!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: chpprguy</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Pat M</div><div class="ubbcode-body">? scope ? </div></div>

+1, mounts, etc? good scope?

If you have an oven, you can try normalizing the barreled action.... </div></div>

This is a bad idea.

If you manage to get your oven hot enough to Normalize Steel (800+*) you have no control over the cooling rate and almost no control over the actual temperature that the oven is sitting at. A normalizing process requires a steady temp within +/-5* to be consistent.

It's not an issue of heat treatment. I suspect the metal work WAY before I would suspect a HT issue.




</div></div>

Thanks bohem,
I should crack a book before I make a comment,
the normalizing is in excess of 1600 F
Andy

 

[NOMISS]

Re: My rifle shoots like a shotgun!

Good advice from Halfnutz.

 

[bohem]

Re: My rifle shoots like a shotgun!

It's very dependent upon **who** made the mauser actions as well as when.

BRNO actions are much more consistent and things like Ankara mausers, Argentine Mausers, and other countries that the Germans were buying from during the war are much better than some of the suspect GEW 98's out there.

Your 'smith is smart to have made the call on that one, glad he didn't get hurt.

 

[RL15]

Re: My rifle shoots like a shotgun!

What is the barrels rate of twist?
And what loads have you tried so far?

 

[Anthony C]

Re: My rifle shoots like a shotgun!

For what its worth. My set up is a 98 Mauser action with a shilen barel. Barrel specs as follows: 4 countour, 1-9 twist cut to 18 inches. On tops sits a Luepold 2.5x8.
I use 120 ballistic tips with fed 210m primers, winc brass (full length resize) and IMR 4064. Also maitianing about a .015 gap jump to lands and grooves. Dont have the charge handy now, but the velocity is right around 2700 (checked several times with a chronograph). Not the hottest load but certianly ample for deer, black bear. My groups are consistantly sub .5 MOA and often really tighter than that. That said it took lots of time to work uo a load. My friend has a similar set and also went through lots of bullets working up. Seems the two guns disliked anything over 120 grains and neither liked the nosler partitions. What wa interesting is that we had similar issues you mentioned sometimes grouped just ok and other times horribly. With the combo i mentioned above things became cosistantly tight. I would guess that a bad group now is just over .5 at 100yds and usauly i can call it. Just our unscientific findings.

 

[JamieD]

Re: My rifle shoots like a shotgun!

I agree with the above. First start with the what could be more common problems and work through the list of potential suspects one thing at a time. Once you have exhousted the list, then it is time to look inward at the barrel, action, chamber itself.

Good Luck,
JamieD

PS - Don't forget to post your results.

 

[nashlaw]

Re: My rifle shoots like a shotgun!

I have a Mark X Mauser action that was rebarreled by E R Shaw in 6.5 Swede. The barrel is nothing great(about the same quality as yours), but suits the need for a hunting stick. It shoots the 120s very well(sub moa), but doesn't do well with anything heavier. After 5 or so shots in quick succession, it will open up a bit, not to the extent your's does.

Even if your rifle has a pencil barrel, I don't think it should go to 8" at 100 even if it is warm.

 

[Greg Langelius *]

Re: My rifle shoots like a shotgun!

I had a Century Arms Mauser that had been restocked, re-barreled chambered in 7.62X39, scope bases, and bolt modified for scope usage. I did every danged thing imaginable to make it shoot. Wouldn't; period.

 

[bohem]

Re: My rifle shoots like a shotgun!

Greg- I'm not surprised, my uncle has an FAL from Century. It hardly functions unless it's fed hot NATO ball with the gas tube wide open. It wouldn't even assemble properly without judicious use of a file on the mating surfaces.

My dad built a k98 from a Turk action in 7.62x39 with the same modifications. His actually would hold 1.25" with Wolf ammo at 100yd. I don't think he ever fed it handloads, it's "just not worth the hassle" according to him...

To the OP, any luck digging out what is going on with it yet?

 

[Greg Langelius *]

Re: My rifle shoots like a shotgun!

Bedded it, pressure pad, handloads, the works, Nada. Took off the scope, hung some string from the sling studs, threw it over my shoulder at a gun show with a 'For Sale - 7.62X39' sign sticking out of the muzzle, took the first offer. $120, and cheap at twice the price.