The Creedmoor Forum

Quote from: bikemutt on August 11, 2022, 09:12:21 PM

Quote from: gman47564 on August 11, 2022, 08:44:45 PMIsnt the sammi drawing of the reamer print telling you that ?

The SAAMI specification shows chamber dimensions which a reamer would have to duplicate. As I said earlier though, I find the layout to be, for lack of a better word, sketchy. The shoulder angle is clearly shown, why not the body angle?
 

Because it is much, much easier to measure diameters at specified locations, when the taper is slight.

The reamer maker can do that and confirm the taper is straight without ever measuring the angle.

We see angle call outs for the shoulder because, from a functional aspect, it is easier to measure the angle to within about a degree when the taper is sharp.

After some confusion, got back in! 

The confusion was because reset password link came in 30-45 minutes after the request was made.  I was worried my account was lost.

An "anteyote"?

Very informative!

Thanks for helping get that great 85 gr bullet on the market!

Excellent point!  Thanks!

Let me rephrase the OP's question:  How much does the optimum seating depth change when one goes from one powder to another?

If the preponderance of experience indicates it changes enough to make a difference, then starting 0.020" off the lands allows a consistent start to things.

If, on the other hand, there is experience suggesting that the optimal seating depth is the same or close to the same for most powders, then starting by optimizing seating depth as the first step might reduce the number of trips to the range during load work up.

Some bullets work just fine at that speed. 

If they are designed as rapid expanding varmint bullets, however, 3170 fps may indeed be a tad fast.

That begets the question: "What bullets a re you using?"

From one vet to another — glad 'ya made it back!

The Forster bench primer looks real interesting.  I have one but haven't used it enough to tell if I like it better than the RCBS I got tired of filling tubes for.

The easy answer is that the most accurate load within 10% of the max load will likely give the best accuracy in the majority wind conditions.

A quick way to check is to calculate the wind drift at 500 yards in a 10 mph crosswind for the 90% and max loads. 

Is the difference more, or less than your nominal group size?  If less the actual load makes no difference as long as it in the most accurate in calm conditions.

Some people would call your 21 shots and thorough clean an adequate break on.

Others are more rigid.

Still others say that break in exercises only use up shots in the life of the barrel.

Probably the best bet os to call your 21 shots the first round of break in and then clean regularly every 20-30 rounds for awhile.

Are the laws dealing with squatters different in Idaho than in California?

My own CA experience is that squatters have more rights than the landownier.

Quote from: Kansaswoodguy on August 05, 2019, 02:09:05 AMMy best advice is buy a complete AR-10 and rebarrel it to 6.5 Creedmoor the DPMS gen 2's are a much smaller frame they maybe the way to go.

This is the best response one can think of given the discussion in the OP.

AR platforms can be surprisingly accurate.  Some makers do better than others.  One way to ferret them out is get on a forum that discusses F-class competition.  Alternatively, rub a search for something like "long range competition accuracy with AR10 rifles."

Who knows, there might even be a credible comment or so in this forum!

Is there a user manual that addresses barrel swaps?

In particular, does the barrel simply screw in with a specified torque or does it use a barrel nut like on the Savage?

Their website talks about improved headspace tolerance, but that is menaingless without a procedural description. 

Does anyone know the max searing depth?  This would nominally be established by the point where the shank meets the nose.