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g n brezinski
08-24-2019, 10:12 PM
given the 100 and 200 yard matches.what are the speeds that these bullets going out the muzzel of your guns ?also is there a length of the barrel that is cocidered perfect for this cartrige?
gary

jackie schmidt
08-24-2019, 11:00 PM
given the 100 and 200 yard matches.what are the speeds that these bullets going out the muzzel of your guns ?also is there a length of the barrel that is cocidered perfect for this cartrige?
gary

You will see velocities from mid 3200 FPS up to 3400+ FPS with 68 grn bullets.

Someone will, sooner or later, mention the old Houston Warehouse declaration of 21 3/4 inches for a length. Thatís a good number, but in truth, barrel length is a non factor as long as the Rifle makes weight.

The best 6PPC barrel I have at the moment is a 2007 vintage Krieger that has been cut off and rechambered twice. Itís 19 inches now.

CCrider
08-25-2019, 04:43 PM
Now that is informative for several reasons. How much do you cut off when rechambering?
Thanks

Mike Bryant
08-27-2019, 01:40 PM
Gary, I cut my barrels for a 22" finished length for no particular reason. Does it make any difference, No. One of the best shooting barrels that I had wound up a little heavy at 22" and I had to cut it back to 21" to make weight. I don't normally shoot with a chronograph and had a Labradar with me in the trailer at New Braunfels early this year. Thought I'd check and see what the load that I was shooting there was running velocity wise and I was getting 3425 fps or thereabouts as closely as I can remember. 30gr of 133 with a 65gr Berger BT. That load has worked well for me at a number of ranges, but it is a hot load and you have to have a full length die that works with your chamber. If I do start getting the click at the top of the bolt stroke when shooting that load, I trash the cases and go to a new batch of brass. At those pressures brass life is short, primer pockets will stretch and what works in my rifle won't necessarily work in someone else's rifle as even as much as we have just about standardized PPC chamber dimensions there is still a lot of difference in freebore length, freebore diameter, neck diameters and clearances and all of that will affect chamber pressures. The biggest thing most overlooked thing I've seen is that you have to have a full length size die that works with your chamber. It has to size the bottom of the case to keep from getting the click at the top of the bolt stroke. If you are getting that, it's a detriment to shooting quickly and will upset the rifle in the sandbags and will have an effect on how well you can run your rifle.

Wilbur
08-27-2019, 05:10 PM
Excellent answers from both Jackie and Mike. Truth is, you're rifle needs to shoot well enough to win and those little "clicks" and such are detrimental to a LARGE extent. Basically, to win, you've got to have a good shooting rifle that works well with the cartridges. I've won a couple of matches when my rifle/case thing was getting out of hand but it's the exception rather than the rule. It's somewhat difficult to achieve but can certainly be done...with a little time and money.

Pay attention to what Mike wrote about when his cases develop a bolt click...new cases!

adamsgt
08-27-2019, 08:59 PM
If you are getting that, it's a detriment to shooting quickly and will upset the rifle in the sandbags and will have an effect on how well you can run your rifle.

Boy does it ever do that.

Boyd Allen
08-28-2019, 01:00 AM
Die click story: I have a Varibase die that has interchangeable base bushings that have almost no chamfer. My shell holder has been shortened by about .013. I had a test case that developed a definite click. Seeing that I had a gap between the shell holder and the bottom of the die, with my die set for the correct bump, I took a chance and unscrewed the base bushing to the point where it just touched the shell holder at the top of the sizing stroke, with a case being sized in place. With the additional reach down the case, the click disappeared, and did not come back after firing.

If you look at a typical FL die there is a huge chamfer/radius at the bottom which limits the die's reach down the case. If the chamber makes contact farther down the case than the die does, you have an area that is not sized. Typically guys use a smaller base die that pulls down the part next to this band far enough that it reduces the unreached area. IMO this is not the best approach. If we work with a faster powder and chamber short, trimming the die, we can do away with the excess chamfer, and improve the coverage of the die relative to the chamber, or perhaps just order a truly custom die that has almost no chamfer.

FBecigneul
08-28-2019, 09:22 AM
This is all the chamfer you need. We also mill our shell holders and have them hardened. We find this is a real clicker fixer.