Bolt Action Help

[Remmy700]

I have a custom remington 700 with a UMSS 26 x 1.25 straight taper barrel in 308 win match. I reload for the gun and have nothing but new lapua brass which I did run in a FL sizer prior to loading. I have reloaded 308 in other rifles a good bit so I am not a novice loader and have good equipment. The action has been trued and bolt lugs and bolt face have been trued. The problem I am having is that when chambering a round it is very firm closing bolt. I have tried factory match ammo as well and it was the same. Is this normal just cause of match chamber or what could it be? Gun has shot great .25 groups and brass has no defects after firing. I used a OAL gauge to set my OAL off the lands a little and thought maybe I loaded the bullets to far out at first but I chambered a non fired sized piece of brass with same effects. Like I said its firm to close bolt not like you have to really force it closed but firm and have not experienced that with any other bolt gun. Any help would be appreciated.

 

[Chawbaccer]

Sounds like the shoulder may be hitting, or the neck is a bit long. You can smoke a case and check.

 

[WNTFW]

Have you tried sizing the brass more? Has it always been this way or is it a new development?

I would take these steps:
Call the rifle builder first.
Clean chamber, lugs, recess and bolt face. Look for brass that has swiped off of head of brass case.
Check the extractor & ejector are functioning freely.
Grease the lugs & recess
Check the front action screw to make sure it is not too long.
Loosen both front and rear action screws and rule that out.
Check action with empty chamber.
Smoke a case and see where it is binding in the chamber.
Check Headspace
Resize brass more
The bolt timing may be off. Also clean inspect lube where rear of bolt contacts action.

 

[Remmy700]

Gun is brand new just had it built. So I have not fired it until the other day and I loaded a bunch up for load developement. I was thinking the shoulder needed to be pushed back more. And bolt is perfect without round and occasionally fine with some handloads about 3 out of 15 function with light bolt throw. Thats what makes me think the shoulder needs to be pushed back a little farther, and the ones that function good are just from the small variation in shoulder distance. I dont know. Slowly but surely will find it out.

 

[fguffey]

If someone thought the neck was in the way, cut it off or shorten it, and be sure the case is not used for anything but testing.
Or use a 243 W case, the neck of the 243 W will not hit anything in fact if you remove the bolt a 243 W can be chambered with a neck of 5 inches+++.
If the case is too long from the head of the case to the shoulder learn to form brass for a short chamber, I form brass for short Chambers that are from .017 thousands shorter than a go-gage length chamber up to cases that are .011 thousands longer than a go-gage length chamber with a standard die and a GOOD press and the versatile full length sizer die, there is no such thing as a difficult to chamber case in one of my rifles, again, when I chamber a rifle, I form cases that are short chamber cases, I am not one of those that do not know where I am when cutting a reaming a chamber.

Bad habit: "I full length sized all my new 'La-per' cases...... then discovered they will not chamber" (without resistance to bolt closing), start with one case, size it then determine if it will chamber, it it does not do not panic and purchase dies that you do not need, learn to measure the chamber length from the bolt face to the shoulder of the chamber and that can not be done with a go, no or beyond gage unless the chamber is shorter than a go-gage length chamber, again I form cases for short chambers in thousands or go-gage length -.001 or -.002 or -.003 all the way down to a minimum length case, the minimum length case is what you get when the die is adjuster correctly to the shell holder in the press.

F. Guffey

 

[Pokyman]

My suggestion is probably not your problem, but should be checked anyway. When occasional rounds chamber just fine and others are hard to chamber, look for a slight bulge in the shoulder of the case that is hard to chamber. If you encounter what you consider bullets that are unusually hard to seat the shoulder of the case may be collapsing slightly as the bullet is seated. This can produce a slight bulge in the shoulder area of the case making the loaded round hard to chamber.

 

[fguffey]

Yes Pokeyman, the discipline of reloading says he check the case after sizing for it's ability to chamber, if the case chambers then does not after seating a bullet the case could have squatted, upset or created a bulge, two causes of bulges, no guide for the bullet on the ride up and or crimping the case mouth around the bullet with more than (just) a hint of contact, as we all know? when crimping a a case there are two things going on, one the bullet is moving down and two the case mouth is closing on the bullet, meaning when the case mouth digs into the bullet when the case moves up the mouth of the case below the crimps opens up and the shoulder that supports the neck bolds.

Measure before and after, measuring before and after will help determine if the shoulder and or neck or both , due to seating a bullet, caused the problem. I am a big fan of datums and the use of the varying diameter tool or tools.

Varying diameter, known to reloaders as an ice cream cone, two types, one flat on the bottom and the other one creates an apex, the flat bottom cone has an apex but is not visible.