Factory ammo tight to chamber

Brambles

Brambles

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I bought a M70 ultimate shadow 300wsm new a couple months ago. Took it to the range and after sighting it in it shot awesome approx 1/2 inch 3 shot groups factory ammo chambered nicely. A few days later I took it to the range and could hardly keep it in 2.5 inches. IIRC the factory ammo still cycled smoothly. So I thought maybe the rifle was moving in the stock since its made of tupperware. I route out some material and drill some anchor holes for the bedding and bed the rifle.

Let the bedding set up for about a month because I had no time to shoot. The other day I went to the range and sighted it in again and continued to shoot 3 shot groups. It didn't shoot great but alright at about 1 1/4 inch consistantly but I noticed the rounds chambered a little tight and it was REAL hard to open the bolt.
Now I know what your gonna say, PRESSURE. But it does it even if I don't fire the round. Its almost like the claw on the CRF is binding on the rim or the headspace has all of a sudded decreased. There is a fine brass powder coming off the brass somewhere but I can't see where. I cleaned my chamber and it seemed to help a little bit but not much. No dents on the neck of the case! No marks on the mouth of the case to suggest too long of brass!

Is this possible, if anyone can help that would be great.

I'm going to try and take the action right out of the stock and chamber some brass and see if the action is getting torqued but I'm not gonna hold my breath.
 
When you check the action in the stock, put some chromic yellow on the action, install and torque - 65in lbs - wait a couple of minutes and then remove the action and see where the high spots are.

Before you do this, recheck the chamber for rough spots and dirt/rust. Make sure the chamber is dry.

Good luck.

RePete.
 
If this is factory ammo it would appear the ammo has quite a variation in tolerances. I have heard poor quality brass has been the biggest problem with the short mags. But....

Have the locking lugs galled? Do they appear smooth or rough? That is all I can think of. Have it inspected before using it any more. Locking lugs should have a bit of lubricating grease on them. Dry and with tight ammo they can gall easily.
 
guntech said:
If this is factory ammo it would appear the ammo has quite a variation in tolerances. I have heard poor quality brass has been the biggest problem with the short mags. But....

Have the locking lugs galled? Do they appear smooth or rough? That is all I can think of. Have it inspected before using it any more. Locking lugs should have a bit of lubricating grease on them. Dry and with tight ammo they can gall easily.
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By the looks there is a little bit of galling on one of the recoil lugs, not much but a little. The chamber looks good. Its probably just bad brass, I noticed one box of brass chambers tighter than the other box. Its winchester Powerpoint 180 gr CPX3 from Cambodian Tire. Probably not the best brass.
I'll have to order some reloading dies and see if I can size the cases down enough to chamber properly.

I loosened off all the screws and tried it again and its still the same, same with it out of the stock. The action is floated on the sides and I can slide paper down each side of the action. I did this because before it was a real tight fit so I fitted it better to avoid action torque.

Thanks

Brambles

Thanks and if anything else comes to mind don't hesitate to yell it out.
 
May have gotten any bedding compound inside the action near the throat area, take a fair bit of oil dump it in there, and work the bolt.Take a visual check in there. The first thing that came to mind was that you had bedded the area of the mag / follower to much for and aft, causing binding, but if no signs of rubbing on the bolt body all should be well when rounds in the mag.
Frank
 
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nope all clean.

The bolt cycles smoothly, but its when you actually chamber brass, then you can feel it gets tight when you cam the bolt closed.

I have checked the chamber and even scrubbed it with a brush because I thought there might be brass or bedding compound in the chamber somewhere but still does it.
 
Brambles said:
By the looks there is a little bit of galling on one of the recoil lugs, not much but a little. The chamber looks good. Its probably just bad brass, I noticed one box of brass chambers tighter than the other box. Its winchester Powerpoint 180 gr CPX3 from Cambodian Tire. Probably not the best brass.
I'll have to order some reloading dies and see if I can size the cases down enough to chamber properly.

I loosened off all the screws and tried it again and its still the same, same with it out of the stock. The action is floated on the sides and I can slide paper down each side of the action. I did this because before it was a real tight fit so I fitted it better to avoid action torque.

Thanks

Brambles

Thanks and if anything else comes to mind don't hesitate to yell it out.
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This isn't going to fix itself. It will probably get worse. I would suggest getting it to a Winchester warranty repair shop if there is any warranty, other wise get it to a knowledgable gunsmith and have it fixed. All the home remedies over the internet are not the way to go in my opinion.
 
It sounds like a tight chamber or rather a minimum headspace chamber. If you intend to reload for this gun try full length resizing your brass and try them for proper chambering. Access to headspace guages might be another way of verifying your guns tolerances.
bigbull
 
It sounds like a tight chamber or rather a minimum headspace chamber.
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I agree with bigbull's call on this.
My Gaillard barreled .22 PPC is very tight on closing a new case the first time; the camming action of bolt closure is bumping the case shoulder back a very slight amount. On second closure of the same case with or wthout firing the closure force is then normal.
 
I'm hearing that Some WSM's don't like some factory ammo, either shooting too HOT or not chambering well.

I have an email to a winchester warranty center right now but haven't heard back yet.
 
Check for a little brass ring just at the end of the chamber, where the casenecks end. Sometimes brass shavings collect there and get pounded in place, taking up the free space. When a slightly longer piece of brass gets chambered, it abuts on that brass and binds.
Try some scrubbing and foaming brass remover or an electronic cleaner.
PP.
 
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