Sticking Bolt Rem 260.

[Chubbs]

Hi Guys
My friend has a Rem 260 based on a Rem 700 action and Krieger barrel. He has been using FC 308 Winchester cases sized down to 260 using a Lee F/L die. He always had tight rounds on chambering so we decided to see what was going on.
We took out the firing pin and ejector and resized the cases until they would drop the bolt into battery without resistance. Then went about finding touch with a .263 PPU 120gr bullet until we had a round which had no resistance on bolt drop. Kept as Master Round.
My friend then sorted his cases and F/L sized them.
The next day we checked a couple of the cases and on seating a .263 PPU 120gr bullet the bolt would become tight on dropping the handle into battery.
We tried a few other cases and had the same happen. No bullet fine. Bullet seated tight bolt.
Tried seating the bullet backwards and deep to prove not jamming into lands but giving same bearing surface on neck. Same problem. Master Round still worked fine.
I took several measurements and found that the new cases where larger OD neck size. Headspace slightly smaller. Trimmed neck down so that OD was smaller than Master Round. Still same problem. this round was now smaller than master in every way. I then noticed that the Master round was a 308 Winchester PPU case.
So we resized another PPU case and it chambered with no resistance.
All measurements on the PPU cases are larger than on the FC cases. Headspace, Neck OD Case Body.
So we can not figure out why the smaller round is causing the resistance.
All cases on their own chamber with no resistance however add same bullet and FC becomes tight even though it has a smaller neck OD.
Anyone experienced this before.

 

[cw308]

Does seem strange but on finding your zero ogive with a stripped bolt on the REM.700 is with the bolt lift do to the resistance on your locking lugs
The case headspace base to datum is with bolt closure. As for the problem are all the measurements the same on both sized bullets?
,

 

[piie]

Did you measure the base of the cases as well - just above the web?

 

[MagnumManiac]

What does a fired neck measure?
I built my Edge with a tight turn neck chamber...gave me fits all up and down from day 1 and then got WORSE.
Discovered the neck clearance I was putting into the brass was too tight, then it developed a carbon ring and pressure went sky high...had to run a different reamer in with larger neck and +P throat.
Anyway, check the neck OD with bullet seated and then check fired case neck OD.
You NEED .004” minimum clearance, .003”‘is tight and less than this is BAD.

Cheers.

 

[cw308]

Yes , I'm shooting a Rem.700 in 308 with a M24 5R RockCreek barrel. Federal brass is on the thick side which I like . Your problem with both sized and seated dummy rounds , if all measurements are the same I don't understand why one should chamber and the other doesn't.. You are using the same bullet. I didn't want to confuse things on the stripped bolt method but when finding you zero ogive setting , seating long and closing the bolt , once your close you will feel the bolt release the pressure on the lugs on the bolt lift just go slow. That's your zero from ogive to bolt face , the case your using should have the .002. I check ogive every 500 fired rounds , lot or bullet change. You will see changes. Keep us informed.
Chris

 

[243winxb]

Donut

 

[EOD Rob]

Donut

Second! Check for donuts! I had the same problem when I necked down Lake City brass for my 260. .264 reamer fixed the problem.

 

[Chubbs]

Thanks for the replies.
The FC are all smaller than the PPU rounds when loaded.
No donuts as FC cases trimmed into shoulder.
All cases have no resistance on chambering only resistance felt on FC cases when bullet seated. Which I would presume would have no effect on the body.
It has me stumped.

 

[gunsandgunsmithing]

Thanks for the replies.
The FC are all smaller than the PPU rounds when loaded.
No donuts as FC cases trimmed into shoulder.
All cases have no resistance on chambering only resistance felt on FC cases when bullet seated. Which I would presume would have no effect on the body.
It has me stumped.

You probably checked it but, how about the brass length..as in trim length?

 

[boltfluter]

If you have access to a lathe start cutting or parting the offending case into pieces. I.e. remove neck, remove neck/shoulder junction etc,etc. You will find the problem guaranteed. Done this several times, and never failed to point me to the offending area of the case. Good luck!

Paul

 

[LCazador]

Hi Guys
My friend has a Rem 260 based on a Rem 700 action and Krieger barrel. He has been using FC 308 Winchester cases sized down to 260 using a Lee F/L die. He always had tight rounds on chambering so we decided to see what was going on.
We took out the firing pin and ejector and resized the cases until they would drop the bolt into battery without resistance. Then went about finding touch with a .263 PPU 120gr bullet until we had a round which had no resistance on bolt drop. Kept as Master Round.
My friend then sorted his cases and F/L sized them.
The next day we checked a couple of the cases and on seating a .263 PPU 120gr bullet the bolt would become tight on dropping the handle into battery.
We tried a few other cases and had the same happen. No bullet fine. Bullet seated tight bolt.
Tried seating the bullet backwards and deep to prove not jamming into lands but giving same bearing surface on neck. Same problem. Master Round still worked fine.
I took several measurements and found that the new cases where larger OD neck size. Headspace slightly smaller. Trimmed neck down so that OD was smaller than Master Round. Still same problem. this round was now smaller than master in every way. I then noticed that the Master round was a 308 Winchester PPU case.
So we resized another PPU case and it chambered with no resistance.
All measurements on the PPU cases are larger than on the FC cases. Headspace, Neck OD Case Body.
So we can not figure out why the smaller round is causing the resistance.
All cases on their own chamber with no resistance however add same bullet and FC becomes tight even though it has a smaller neck OD.
Anyone experienced this before.

Sounds like you're pushing out a donut on the inside of the brass making the neck thicker. Turn the necks.

 

[243winxb]

I sized some GI 308 nato down to 243 win. Neck reamed and neck turned. Still chambered hard.

 

[cw308]

Using the same bullet seated in both brands of brass the neck OD is the same , base to datum line is the same and base to ogive is the same. It's not the donut effect after checking . I'm sure you've checked trim length ,
The federal cases were 308 cases sized down , is there a difference in the shoulder angle? , same measurement from base to start of shoulder?
PS : Reading your answers , it only happens with seated bullets . That
through what I just posted out the window. Sorry for asking but your chamber and barrel are clean . Maybe a shot of JB Compound , This sure is an ass kicker.

 

[JFrank]

NSJ has probably been mentioned already but that is worth a look as well as the angle

 

[338 dude]

Hi Guys
My friend has a Rem 260 based on a Rem 700 action and Krieger barrel. He has been using FC 308 Winchester cases sized down to 260 using a Lee F/L die. He always had tight rounds on chambering so we decided to see what was going on.
We took out the firing pin and ejector and resized the cases until they would drop the bolt into battery without resistance. Then went about finding touch with a .263 PPU 120gr bullet until we had a round which had no resistance on bolt drop. Kept as Master Round.
My friend then sorted his cases and F/L sized them.
The next day we checked a couple of the cases and on seating a .263 PPU 120gr bullet the bolt would become tight on dropping the handle into battery.
We tried a few other cases and had the same happen. No bullet fine. Bullet seated tight bolt.
Tried seating the bullet backwards and deep to prove not jamming into lands but giving same bearing surface on neck. Same problem. Master Round still worked fine.
I took several measurements and found that the new cases where larger OD neck size. Headspace slightly smaller. Trimmed neck down so that OD was smaller than Master Round. Still same problem. this round was now smaller than master in every way. I then noticed that the Master round was a 308 Winchester PPU case.
So we resized another PPU case and it chambered with no resistance.
All measurements on the PPU cases are larger than on the FC cases. Headspace, Neck OD Case Body.
So we can not figure out why the smaller round is causing the resistance.
All cases on their own chamber with no resistance however add same bullet and FC becomes tight even though it has a smaller neck OD.
Anyone experienced this before.

Any data collected must be for the same bullets occasionally even the same lot of bullets and this definitely would apply to brass the quick and cheap (redneck method if you will as I am a redneck I guess) color the entire bullet with a black sharpie chamber it pull it out see were it rubbed off that will indicate your problem area

 

[JFrank]

Farm boy technology at its finest...

 

[JFrank]

Of course one could always order a cut away Sheridan gauge, ( you can see exactly where the case is making contact) no more problem....

 

[Chubbs]

Thanks once again for replies.
All cases trimmed with Lee cutter to 2.0150" a bit short in my opinion but that,s the Lee Trimmer for you.
No access to a lathe
FC neck OD .292" even trimmed down to .290" with bullet
PPU neck OD .294 with bullet
Will check shoulder angle when I see him next.
Will try sharpie again but first time didn,t show anything obvious.
Didn't check chamber as there was no problem with the PPU and he assured me it was clean. Will revisit this.
I am determined to find out what is happening although mate is going over to the PPU's.

 

[Coyotefurharvester]

I think I know the answer, but does he have any new factory brass/ammo for comparison?

 

[johnfred1965]

FC brass can be soft. the sized case fits but with a bullet is tight. Any chance the shoulder is bulging a bit when seating the bullet in a softer case?