NugginFutz Wrote:Tedward,
I would like to clarify the point you're making, in that last comment. Not every Grendel chamber needs to be hand lapped - far from it. The sample of barrels with this issue is quite small, considering how many Grendels are out there. It is not a function of the chamber design, but rather a function of how a particular reamer was designed.
So, when you say "other calibers may not need (lapping)" because their throat geometry is different than the Grendel's, the implication is that a Grendel would need lapping. This is simply not the case. I am sure you did not mean to imply that all Grendels need to be lapped, and wanted to make certain that point is clear.
Yes that is true and I am not trying to imply anything. If the reamer manufacture makes there reamer in the throat area on the low end of tolerances, +/-.000 and does not decide to go on the +.001 or +.002 side, that lapping may be needed or a tight throat is likely to be present till it is broke in or wears some. I think, and it is just me saying this, for good practice the reamer manufacture might want to make there reamers on the + side so if and when the reamer does wear .001, it will still cut to the minimum of .000. Again just a point I would have never thought about until this topic came up.
Maybe some reamer manufacturers noticed this a long time ago and do make their Grendel reamers to the +.002 of the tolerance to maintain the SAAMI chamber spec or what ever it is and not have the issue we have seen. Maybe being proactive from past issues. Don't know, just a thought.