I'm not getting consistent C.O,A.L. with SMK's

[Anvil]

I have a question for you guys, I have been reloading 175gr SMK HPBT for a few months now. I try to keep my C.O.A.L. at 2.830. I have noticed from the start that my COAL always varies between 2.828 and 2.835. Quite frankly it's driving me crazy because accuracy and consistency go hand and hand. I can't help but think I am sacrificing accuracy because of the inconsistency. Can anyone please elaborate on this subject for me. Is there anything I can do to fix this. Or am I overthinking this?

 

[Advokaten]

Re: I'm not getting consistent C.O,A.L. with SMK's

You are of cours measuring at the ogive,

the important place of the round?

Tips may vary in lenght on SMK, making them have a slightly varying lenght.

Best regards Chris

 

[sp388]

Re: I'm not getting consistent C.O,A.L. with SMK's

The SMK is commonly known to have different lengths- for possible theories as to why you can see many a post here by searching. Many say it is because the way the put on the copper jacket from the bottom up - - - either way or whatever the reason- this is why many people use a tool to measure at the OGIVE such as the sinclair nut. This gives you a consistent distance from seating depth until the bullet sinks into the rifling when fired. This is also why many guys buy there bullets in 500 count lot numbers. For you as of now (without ogive nut and one large number of bullets from the same lot) -- you can try weighing and measuring each bullet you will use and attempting to seperate them into your own different lots.

It also may be your bullet seating die. I use the redding competition seater and be sure to keep the inside bearing/seating surface clean. This will seat a bullet using its bearing surface / ogive which also takes the different length "tip" or points out of play.

 

[Big Dog Steel]

Re: I'm not getting consistent C.O,A.L. with SMK's

Get a tool to measure from the ogive. There are probably better tools for the job, but I use a RCBS precision mic and I also use a hornady (Formerly stoney point) OAL gauge. Both tools seem to work, ok. Your other option is trimming the meplats. There are lots of tools available for this,however, if you go this route you will lose 2-3% of the b.c., its not much but it makes a small difference if you are shooting LR. I had the same issue as you did with the 175 smk's. Eventually I just changed to 168 & 178 A-max's. Polymer tips don't vary, and for me are easier to dial in on my dies.

 

[Anvil]

Re: I'm not getting consistent C.O,A.L. with SMK's

Thanks for the help guys. I will now go out a buy another specialized tool. LOL.

 

[sp388]

Re: I'm not getting consistent C.O,A.L. with SMK's

Which one - the sinclair nut or the bullet micro competition seater ?????

I say both !!

 

[Advokaten]

Re: I'm not getting consistent C.O,A.L. with SMK's

Or

you could just use a case from a 243 Win or other 6 mm round, hell yes even a 6,5x55 case would do,

invert, set on top of loaded round and measure.

I am sure that you will find that you are GTG and that said part of your reloading/shooting is not the cause for concern.

Are you made of money and like to spend it, sure why not your economy needs it.

Best regards Chris

 

[Anvil]

Re: I'm not getting consistent C.O,A.L. with SMK's

I will have to try the A-max's also. Thanks again..

 

[Anvil]

Re: I'm not getting consistent C.O,A.L. with SMK's

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Swedish guy</div><div class="ubbcode-body">Or

you could just use a case from a 243 Win or other 6 mm round, hell yes even a 6,5x55 case would do,

invert, set on top of loaded round and measure.

I am sure that you will find that you are GTG and that said part of your reloading/shooting is not the cause for concern.

Are you made of money and like to spend it, sure why not your economy needs it.

Best regards Chris</div></div> Love the out of the box thinking. I'll try this first. Thanks..

 

[sp388]

Re: I'm not getting consistent C.O,A.L. with SMK's

Swedish guy---- our economy

They say money is the root of all evil ..........

so if we are all broke- we must have a country full of really nice people !! ?? **

 

[Wil]

Re: I'm not getting consistent C.O,A.L. with SMK's

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SP308</div><div class="ubbcode-body">They say money is the root of all evil ..........</div></div>

Incorrect... The correct quote is:

1 Timothy 6:10

For the LOVE of money is the root of all evil...