COAL questions

[desertrat1979]

I am playing around with some 190SMK's right now and I am wondering what COAL is the average. I have the factory 24" sporter barrel w/ 1-10 twist. I loaded some the other day, shot a 1.5" group @ 100 yds. I used the zero I set for my 155 SMK's. The hits were like 10" lower. I had them at 3.320 coal with 58gr of RL22. I worked up another batch today and noticed the case is pretty full with 59.5gr of RL22. I have the COAL @ 3.448. Does this sound right? The rounds chamber smoothly and there isnt any case bulging that I noticed.

 

[Sig685]

Re: COAL questions

Given the COAL listed and the amount of powder, I suspect you are not talking about .308 Winchester. Perhaps you should change the title to "Guess what cartridge I'm talking about."

 

[desertHK]

Re: COAL questions

Judging from what you are saying are you talking about the 300 WSM? Also, what is your chamber length? I always like to know the total chamber length first and kind a work backward from that to see what COAL will give me the best grouping.

 

[desertrat1979]

Re: COAL questions

Whoops, its a 30-06. Sorry about that. I do not know the length of the chamber.

 

[MitchAlsup]

Re: COAL questions

To find the length of the chamber: (Where bullet touches lands)
A) size one piece of brass
B) seat a bullet in the unprimed unpowdered brass so that it is just barely held by the neck (More than 0.150 longer than normal)
C) place case+bullet in chamber and then carefuly close bolt
D) with extreme care, extract case+bullet
E) measure OAL

This OAL will be within a couple of thou of the length of your chamber with a case sized just like that using that particular bullet.

Repeat measurement at least 3 times and get reading within 0.002 before accepting that this reading is anywhere near accurate.