Dirty Boi

[Corjack]

I have been getting along real well with the 6.5x47 easy to load and accurate. Only complaint it that about 60 rounds into a match I will get an occasional heavy bolt lift. After a match I can clean it, then runs good until I get another 60 rounds through it. Finally figured out that the CIP reamer used in both my barrels only allows for .002 neck clearance . I can barely push a bullet into a fired case. And then it has enough tension to almost hold the bullet well enough to load it and shoot it. I figure my brass that have 4-5 firings are thickening up just enough that when it gets a bit dirty, there is just not enough clearance. Kinda hard to stop and clean a barrel in the middle of a match, and I sure as heck am not going to neck turn nearly 800 brass. Consensus is with everyone that I trust, ..002 clearance is not enough. I called JGS Tuesday and ordered a CIP reamer that is plus .002 in the neck. No other changes. Got the print for approval yesterday . Hopefully have it in about 4 months. I will switch back to the 6 BRA and 223 until I can get the reamer and open up,the necks . Also talked to my 600 and 1000 yard benchrest buddy’s, and all of them said that the .004 clearance I will have is considered excessive.

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[SPEEDY]

Interesting problem to have, probably brilliant for an F class match but not so in a high volume shoot like that.

[dchamp]

I have no clue about what will happen after opening up the neck in your chamber, probably nothing. These are just a couple of questions that pop up in my mind. What affect if any will this have on accuracy? If fowling the chambers neck area is causing problems with bolt lift, would trying a different powder the may burn cleaner be an appropriate first step in resolving the issue. It will be interesting to see how things turn out.

[Rifletuner]

Also talked to my 600 and 1000 yard benchrest buddy’s, and all of them said that the .004 clearance I will have is considered excessive.

I dont think that clearance is considered "excessive" in all circles of benchrest. Its certainly recognised that tight case necks will cause random flyers, hence the phrase "turn thin to win". I think you have correctly identified your issue. If I couldnt easily drop a bullet into a fired case, I always turned more off the necks.

[Corjack]

I have no clue about what will happen after opening up the neck in your chamber, probably nothing. These are just a couple of questions that pop up in my mind. What affect if any will this have on accuracy? If fowling the chambers neck area is causing problems with bolt lift, would trying a different powder the may burn cleaner be an appropriate first step in resolving the issue. It will be interesting to see how things turn out.

Unfortunately there are only two powder choices that work super consistently. Varget and H4350. I am right in the node with 36.5 grains Varget.

I think considering the accuracy and SDs I am getting now, that I should see little change in accuracy. Probably if anything it will lesson fliers. When you are shooting at a piece of steel 500-100 yards it is kinda hard to tell if a miss was a flier or shooter error. I am just not changing the setup that much, should do nothing more than increase consistency.

[John0313]

Fitted necks for a 60 shot string is asking a lot. I would take a lead from the 300 Meter discipline, where .004-.005 clearance is more the norm (6 BR). More powder means more powder fouling, so consider yourself forewarned!!

[Corjack]

Fitted necks for a 60 shot string is asking a lot. I would take a lead from the 300 Meter discipline, where .004-.005 clearance is more the norm (6 BR). More powder means more powder fouling, so consider yourself forewarned!!

That’s exactly what I am doing . Going to .004 from .002. We actually are shooting in excess of 80 rounds in a one day match without cleaning. Some two day matches may go 230 rounds counting the tune up.