6.5 Creedmoor freebore problem

[22XC]

My 6.5 Creedmoor reamer is a "match" dimension reamer from PTG with a .295" neck and .199" FB. I used this several years ago & everything was OK. Today, I chambered a Rock .256/.264 5R barrel and learned the FB is at least .060" too short for Nosler 140-gr BT factory ammo with a 2.8" OAL. When chamber, the bullet is forced into the lands & the marks made by the lands are about .060" long. Hornady factory match ammo with the 142 gr ELD is also difficult to chamber. I know I can increase the FB with a throating reamer but hate to lengthen the throat, since .199 FB is SAAMI & seems to work well with other ammo. I'd appreciate a recommendation: to extend the throat or not. Or could the Nosler factory ammo be out of spec.?
Many thanks.
Roger

 

[Alex Wheeler]

Diameter, You should be able to tell with the bore scope

 

[Walt Krafft]

How does it shoot?

 

[Ksracer]

Chances are the reamer "chattered" in the rifling and cut a pentagon shaped hole for the freebore. The inscribed diameter of the hole across the inside points is smaller than .264". You may be able to clean it up using a spiral throater. The ones I've bought from Manson are usually .001" over nominal, whereas chamber reamers are usually only .0005" over on FB.

 

[DaveTooley]

Do you cut the complete chamber with the finish reamer? Just one thing to check is wear on the throat area of the reamer. It doesn't take much to go from .0005" over to an almost interference fit.