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TREERAT
04-14-2009, 12:00 PM
If I can reach the lands with only the forward greese groove exposed would this be better than 30 thousands bullet jump with groove covered? with 3 greese groove bullet, if it is better to be into the lands, should I put lube in the forward groove or leave it empty? velocity will be between 1200 to 1400 fps.

Shiloh
04-14-2009, 12:14 PM
Maybe.

What boolit/boolits are you speaking of ??

SHiloh

Nora
04-14-2009, 12:21 PM
Also what are you shooting them with? I've got a couple of mil surps that will sit .030" of the rifling to be able to be cycled threw the mag well. This hasn't stopped them from producing shot groups that I am happy with.

BABore
04-14-2009, 12:56 PM
If I can reach the lands with only the forward greese groove exposed would this be better than 30 thousands bullet jump with groove covered? with 3 greese groove bullet, if it is better to be into the lands, should I put lube in the forward groove or leave it empty? velocity will be between 1200 to 1400 fps.

Let's see;

into the lands, with lube groove exposed, with lube in it.

into the lands, with lube groove exposed, with no lube in it.

30 thou off, with lube grooves covered, all with lube in them.

30 thou off, with only two grooves lubed.

30 thou off with only one groove lubed.

There's only one source that will give a correct answer.

Your Gun!

Load up some sets and see what works best.

TREERAT
04-14-2009, 01:38 PM
I guess I will just have to try and see what works in my gun. I only wanted to know what generaly worked better in most guns. I know all guns will show preferences, but what generaly works is usualy a good starting point.

leftiye
04-14-2009, 01:42 PM
Depends if you can keep the lube clean in the exposed groove(s). If you can I personally would do it. As has been mentioned, will it function through the action when set up thataway - may make a difference also.

BABore
04-14-2009, 02:10 PM
It's not so much what generally works. It's what you miss in the process. If someone told you to "do it this way" and it worked ok or good enough, would you ever go back and try the other variations? Could you be leaving something on the table? You'll learn alot more by doing it and can then apply what you learn to other things.

Seating depth is one variable. Genrerally you don't want much, if any, running room with cast. But, there are times when it can work. Sometimes better. How many grooves to lube can also depend. Your running rather low velocity at 1,200 to 1,300 fps. Not much lube needed there. Of course this would depend on the boolit's lube capacity, bearing length, hardness, barrel, and lube quality. You don't always want a filled lube groove exposed so it can pick up crap. With a low quality lube, you may have to fill all the grooves or maybe just two of them. With a higher quality lube, you may only have to fill one. This would leave two grooves open to help wipe fouling out. May or may not make a difference. Won't know til you try it out. Change lube, start over. It all comes down to what you expect for accuracy.

TREERAT
04-14-2009, 02:48 PM
I did not intend to sound grumpy or ungratefull for your advice. it is just hard to run to the range to fire a few rounds to check one variable at a time, even tho it is the best way to do it. so I was only being lazy and cheep and trying to cut corners to get to the best starting point and develope from there.

JSnover
04-14-2009, 04:39 PM
It's easy. If your variable of choice is seating depth, seat 15 rounds to three different depths; five touching the rifling, five 30 thousandths out and the other five somewhere else. See what your rifle likes. My single shot loads are seated long with no crimp. The rifling acts as a stop for the boolit, the case is pushed forward by the breech block. A perfect fit every time.