Barrel Extremely Heat Sensitive

[jackstrawIII]

Hey guys,

I have a Win Model 70 in 270 WSM. It's glass bedded in a McMillan stock... and I'm still having issues with heat sensitivity.

My first shot is always where I want it, but any follow up shot without letting the barrel cool for a matter of minutes will be way off whack. I'm talking literally, first shot is good, second shot will be 3-4" away at 100 yards.

But, if I let the barrel fully cool, it goes back to right where I want it. I know it's not my shooting... but this gun is so temp sensitive I can't believe it.

Anyone have an experience with a gun like this? Is this a problem with the heat treat or stress relief of the barrel, or should I just accept this as normal and move on with my life? It makes it very difficult to test out loads and such.

Thanks.

[Dufus]

I don't have any experience with the 270 WSM, but I do with M70s.

I have never experienced that issue with any of mine or buddies that I shoot with.

Possibly there is something touching under the barrel to throw it off.

With the screws out of it, can you detect any movement forward and back in the barrel to stock relationship? If so, re-bed the recoil lug.

A buddy bedded his stock and didn't get the recoil lug good enough and it would move ever so slightly.

Run a card between the barrel and stock to see it there is clearance back to the receiver.

[jmr40]

Could be improperly bedded or the barrel touching the stock when it gets hot.

When was this rifle made? Is it a new production rifle or one made in New Haven? How did it shoot before changing the stock?

The Winchester Classics made in the 1990's are very good rifles, but starting around 2000 or so quality started declining up until Winchester closed the New Haven factory in 2006. The WSM's didn't come out until about 2000, just about the time quality started sliding. If it is one of the older guns that may explain the problems.

I used to have a 2006 production Winchester 300 WSM. Mine wasn't as good as the ones I owned made in the 1990's, but it gave no major problems. Certainly not the issue you describe. I liked the rifle a lot, but rarely used it, didn't need it, and had a chance to sell it at a small profit so I let it go.

For the most part the Winchester rifles made 2008-present after being bought by FN are pretty good.

[HiBC]

I'm not sure how productive it will be to guess about this.
Any production process CAN let a lemon escape. An internal stress issue isn't something you can see. But it could be there.

I once bought about six take-off rifle barrels from a custom rifle maker.Rem,Ruger,Win... I hold Winchester in high regard,this is not a bash on Winchester.I don't know any history on the barrel,a .308 M-70 barrel,but the hole through the middle just was not straight. It was obvious just looking through the bore. In this case,the thin wall side would heat faster and expand more. If it happened once..

[603Country]

When I was working, back in the 80’s, I also guided deer hunters on our two huge ranches. One of the guys I used to hunt with had a Rem 700 in 243 that was like the OP’s rifle. First shot was good, but any follow up shots went high and right drastically. Floating the barrel didn’t help, and nothing else helped the situation. I think it was just a bad barrel. It happens. I’d have it rebarreled or sell it and buy something else.

Still, if you can get the job done with one bullet, you’re Ok as is. But i’d rebarrel it.

[Mobuck]

"Could be improperly bedded or the barrel touching the stock when it gets hot."
One shot from a cold barrel won't make it hot.
I think the barrel is messed up. I've seen POI shift from cold clean bore to fouled bore of up to 2" but a 3-4" shift between cold and warm is unacceptable.

[CarJunkieLS1]

It's a bad barrel most likely. Does the 3rd shot land close to the second shot? My feeling is that the barrel is "off center" to the bolt face.

I had a rifle that behaves similar to this and the barrel wasn't center to the bolt face. It was off .011 of an inch. Took a new barrel to fix it.

[tobnpr]

I tend to think it's stresses in the steel as you suggested, because every other likely culprit is ruled out.
Can't be bedding, free-floating, action screws, optic etc. because the ONLY "change" is time between shots.

This is assuming the repeatability of the problem. If what you describe happens consistently I see no other possibility- though I'll admit I've never encountered such sensitivity to heat.

Mixed opinions on cryo stress relief after the fact, how old is the action/barrel?

[jackstrawIII]

Unfortunately, it seems like consensus that there's something wrong with the barrel, which I'm inclined to believe. Something just feels wrong with it.

Now, I have to decide if I'm going to stay with 270 WSM on the re-barrel, or switch to 7mm WSM. Choices, choices.

[RC20]

How often do you need a second shot?

It might be just fine for hunting, just annoying target shooting. All but one of my hunts were one shot kills.

Maybe not a great answer but maybe fully workable as well?

Any follow up shot as long as its consistent you can adjust on the animal.

I will disagree on barrel aspects. I have a 270 pencil barrel I am playing with, first shot is dead on (of course) but the next two shift off to the left 1.5 to 2 inches. So, while you may not feel the external heat, there is a lot of heat inside working its way out.

Not as bad as yours but the same pattern.


A tight barrel will be worse.


Full cool down as you noted and its back to the original spot. I would be ok hunting, just not target.

As I got the gun for the action, I may even cut the barrel down and see if that changes the dynamics.

[603Country]

To go a bit further with my comments (and opinion), I would swap the barrel out or get another rifle. Life’s too short to have an off-spec barrel. I have a couple of pencil barrel rifles, and some heavier barrels, most of which are high dollar replacements. None of them have any bizarre heating/accuracy issues. And, prior to the new barrels, none of the original barrels acted odd either.

And, on the subject of barrels, i’m fond of 20 inch barrels, with a slightly heavier contour. My Tikka 260, with a #4 Brux barrel will shoot 100 and 120 grain bullets into the same small group and will do it again and again and again.

I would not be happy with a rifle that was not extremely accurate or sprayed the second bullet. Sometimes I need that second bullet, and it needs to go where it’s aimed.

[jackstrawIII]

All but one of my hunts were one shot kills.

This has been my experience thus far, but I don't really want to count on that, especially for a gun I intend to use on a future big game hunt.

I would not be happy with a rifle that was not extremely accurate or sprayed the second bullet. Sometimes I need that second bullet, and it needs to go where it’s aimed.

Yeah, well said. I feel like life is too short to screw around with stuff that doesn't work. If I can't fix it... well then I need to fix it.

[reynolds357]

Action needs to be blueprinted. That WILL cure your problem. Winchester are notorious for being off center axis.

[Paul B.]

"I have a Win Model 70 in 270 WSM. It's glass bedded in a McMillan stock... and I'm still having issues with heat sensitivity."

Well, I've seen all the questions and suggestions posted so far with one exception. You say it's glass bedded. Is this just the action or action with about two inched of the barrel where it joins the receiver or was this a full bedding job including the barrel all the way to the end of the forearm?

To explain my question, years ago a friend made me a custom rifle on a Mauser action in 30-06. Full action and barrel bed to the end of the forearm. Off and on, for years I tried to make that rifle shot something that could be called a group. I finally bedded the rifle in a McMillan, bedding action and the first two inches of the barrel at the receiver. Today, I can shoot three shots as fast as I can from the bench and groups run in the near .375" to .50 range. Add two shots for five total and the groups are still one inch or slightly less. Yes, the barrel is now free floating and that cured my rifle.

I can't say this will fix your problem but it's something to look at. Good luck at finding the fix.
Paul B.

[jackstrawIII]

Hey reynolds357,

Do you have any sources on who could do this? No smiths in my area of capable of doing real work like this, and most of the barrel makers (Hart, ER Shaw, PacNor) say that they will "square action face" or something like that... which doesn't appear to be a true blueprint.

How does one go about this?

[jackstrawIII]

Paul B,

It's bedded at the recoil lug and the rear screw area (not sure the official term). It is free floated along the entire barrel.

[reynolds357]

Do you have any sources on who could do this? No smiths in my area of capable of doing real work like this, and most of the barrel makers (Hart, ER Shaw, PacNor) say that they will "square action face" or something like that... which doesn't appear to be a true blueprint.

How does one go about this?
__________________
A gunsmith with a lathe can do it. It is possible to do without a lathe, but much easier on the lathe. To oversimplify it, You line bore and straighten the action threads. You then true the face of the action. You then true the barrel threads, finish ream, etc. Going rate around here is $150 to $200. I don't see sending it to Ga. To have it done. Sure someone on here can tell you someone in your area.

[RC20]

Yeah, well said. I feel like life is too short to screw around with stuff that doesn't work. If I can't fix it... well then I need to fix it.

Fair enough. I could live with it if it was just a hunting gun and hoofed game.

Now if it came down to shooting at a Cape Town buff, I would want as much accuracy as possible.

Other critters would depend on how rare chance was, cost of hunt etc.

Lot of people shoot Ruger 1s, thought it was worth a thought.

Cheaper to buy a Savage than fix it though.

Barrel something north of $300 I would think and gun smith fees to install it and true it up.

[old roper]

How the rifle shoot before changing out stock? When the Win WSM first came out, I got one 270WSM and had McMillan put on and I never fired it. After 3 shot it was back to gunsmith and I had Broughton barrel put on solve problems.

That barrel may not like being free floated. That Broughton barrel was bedded about 1 1/12" forward of the lug. I've got Win 70 30-06 with Bartlein barrel in McMillan stock and it's bedded same way and both stock have pillars from McMillan. Work was done by 2 different gunsmith

[cw308]

I'm sure you checked but have to ask , if shooting with a scope , did you check with another scope or mount screws loose . Your starting out with a clean dry no oil in the barrel shot is on target .Why the first cold bore shot is on target an the next few went south , are you sure its not your hold . I just want to cover all bases . I shoot bench rest only , if you did everything everyone suggesed above an looking for a place to send your rifle . Give Accurate Ordnance a call their located in GA. I sent my rifle to them they installed a new barrel & completely blueprinted in 6 weeks door to door. Hope I Helped in some way , Chris

[taylorce1]

If your receiver and barrel are out of alignment you can have the problem you are describing as has already been eluded to. Most competent gunsmiths can "Blueprint" an action for around $300. What I expect out of a blueprinted action is squaring of the receiver and bolt face, lapping the bolt lugs, re-cutting of the threads on the receiver, and polishing all the raceways, rails, and feed ramp.

This may or may not require a new barrel, it all depends on how your old barrel is mated up to your current receiver. Three things could happen, your old barrel could be used as is with just a touch up on the head space. Your old barrel may need to be set back, recut the threads, rechamber, and headspace. Last and most expensive is a new barrel in your choice of chambers, but I'd probably keep it a .270 WSM as it is more popular.

[AlaBusa]

Have the barrel pulled and cryogenically stress relieved and stabilized. Problem solved.

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[AlaBusa]

Originally Posted by tobnpr

Mixed opinions on cryo stress relief after the fact, how old is the action/barrel?

My Sako .300 Win Mag is cryo stress relieved and stabilized. I can run through an entire box of shells and the poi never changes. The barrel will be hot enough you can't hold onto it with a bare hamd.


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[T. O'Heir]

"...Floating the barrel didn’t help..." Floating the barrel guarantees absolutely nothing.
It's a bedding issue. How close does a dollar bill fit between the stock and the barrel? Like jmr40 says, it may be close enough to be touching with the heat of that one shot.
Oh and the dollar bill, if the thing is floated, should not touch anywhere up to the chamber area of the barrel. However, like I said, floating a barrel guarantees absolutely nothing. Some rifle just don't like a floated barrel.
Old roper's question about how the thing shot with the original stock will tell you a bunch too. If the rifle was fine before you changed the stock, that's your answer.

[AlaBusa]

Originally Posted by T. O'Heir

"...Floating the barrel didn’t help..." Floating the barrel guarantees absolutely nothing.

Actually, some rifles shoot much better with a little contact between the barrel and stock. Especially the smaller contour barrels.

If a dollar will slide all the way in, take a piece of notebook paper, fold it double and see how far it goes. If it goes halfway or less, get it snug and go shoot. See if it helps.


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