Home Forums Hunting & Shooting Gunsmithing Reamer modification on 6mm

The chamber on an improved 6mm I have has 150 thou freebore which is way too long for the new pointy 90 grain Sierra TGK. It's ok for the less pointy projectiles that have a much lower bc. I run out of magazine length 3.04" and also neck length because of the aggressive boat-tail when trying to seat near the lands. Accuracy is poor because of this. I'm wanting to set the Model 70 barrel back 2 threads (total 0.125") and recut the chamber. I'm assuming I probably need to get a new reamer with around a 0.020 to 0.040" freebore. Would if be really difficult to modify my existing reamer either so it has a reduced throat or no throat at all so it just cuts the chamber without the throat? If it didn't cut the throat then the barrel set back of 2 threads would be just right. Thank you.