What do you guys consider to be acceptable deviation in your preset COAL. No matter what I try as well as 2 different brands of seater dies I can't get less than .003 deviation and sometimes as much as .005 particularly with .224 and 308 SMK's
COAL Acceptable Deviation?
- Thread starter samnev
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Re: COAL Acceptable Deviation?
What seater dies are you using? Are you just using a set of calipers to measure the overall or are you using an o-give gauge? Try a set of Redding or Forster competition micrometer dies with the o-give gauge this seems to work well for me and alot of others. I rarely see a .001 dfference. I have never seen that much variation with SMK's when only checking the o-give, but you will if your measuring the tip to base the Bergers, and SMK's all differ in overall length because of the way they are formed which won't effect overall perfomance of the bullet. Hope this helps.
What seater dies are you using? Are you just using a set of calipers to measure the overall or are you using an o-give gauge? Try a set of Redding or Forster competition micrometer dies with the o-give gauge this seems to work well for me and alot of others. I rarely see a .001 dfference. I have never seen that much variation with SMK's when only checking the o-give, but you will if your measuring the tip to base the Bergers, and SMK's all differ in overall length because of the way they are formed which won't effect overall perfomance of the bullet. Hope this helps.
Re: COAL Acceptable Deviation?
If you want to load to an exact COAL do the procedure that follows.
A) seat all your bullest at least 0.050 too long
B) repeat for each bullet individually
C) measure COAL of one bullet
D) dial in correction on competition micrometer
E) reseat one bullet
F) go back to C if you have more bullets
I can get 0.001-0.002 when doing this.
However, it is completely UNNECESSARY to get the COAL this tight. Bullets vary in length, bulets vary in the curvature on the ogive. So the above procedure is compensating for the variations on the shapes of the individual bullets.
What you really want is to get the ogive position correct, this sets the jump distance. Consistent jump distance is the key, not consistent COAL. To do this all you need to do is to run a batch of bullets through the competition seater die with one setting on the micrometer. That is why these dies were created.
If you want to load to an exact COAL do the procedure that follows.
A) seat all your bullest at least 0.050 too long
B) repeat for each bullet individually
C) measure COAL of one bullet
D) dial in correction on competition micrometer
E) reseat one bullet
F) go back to C if you have more bullets
I can get 0.001-0.002 when doing this.
However, it is completely UNNECESSARY to get the COAL this tight. Bullets vary in length, bulets vary in the curvature on the ogive. So the above procedure is compensating for the variations on the shapes of the individual bullets.
What you really want is to get the ogive position correct, this sets the jump distance. Consistent jump distance is the key, not consistent COAL. To do this all you need to do is to run a batch of bullets through the competition seater die with one setting on the micrometer. That is why these dies were created.
Re: COAL Acceptable Deviation?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MitchAlsup</div><div class="ubbcode-body">
<span style="font-weight: bold">What you really want is to get the ogive position correct, this sets the jump distance. Consistent jump distance is the key, not consistent COAL. </span> </div></div>
This.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MitchAlsup</div><div class="ubbcode-body">
<span style="font-weight: bold">What you really want is to get the ogive position correct, this sets the jump distance. Consistent jump distance is the key, not consistent COAL. </span> </div></div>
This.
Re: COAL Acceptable Deviation?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: buffybuster</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MitchAlsup</div><div class="ubbcode-body">
<span style="font-weight: bold">What you really want is to get the ogive position correct, this sets the jump distance. Consistent jump distance is the key, not consistent COAL. </span> </div></div>
This. </div></div>
Yep!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: buffybuster</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: MitchAlsup</div><div class="ubbcode-body">
<span style="font-weight: bold">What you really want is to get the ogive position correct, this sets the jump distance. Consistent jump distance is the key, not consistent COAL. </span> </div></div>
This. </div></div>
Yep!
Re: COAL Acceptable Deviation?
same thing with SMKs. I just seat to 2.800...when my caliper says this I stop and lock it down. Then I just keep a constant speed/pressure on the press handle. Never had an issue down range all .5 or under. Yep when I meassure some like ten in a row it will be up and down..but think about it..the Die is "locked down" so it has to be the bullets. Set it and forget it...this is if your running mags and not loading for BR then you can messure your heart out to .0001. Good Luck.
same thing with SMKs. I just seat to 2.800...when my caliper says this I stop and lock it down. Then I just keep a constant speed/pressure on the press handle. Never had an issue down range all .5 or under. Yep when I meassure some like ten in a row it will be up and down..but think about it..the Die is "locked down" so it has to be the bullets. Set it and forget it...this is if your running mags and not loading for BR then you can messure your heart out to .0001. Good Luck.
Re: COAL Acceptable Deviation?
Thanks guys for the replies. The 223 52 and 69 smk were the main problem, not so much the 168 gran SMK's. But I ordered Forster Micrometer seating dies for both.
Thanks guys for the replies. The 223 52 and 69 smk were the main problem, not so much the 168 gran SMK's. But I ordered Forster Micrometer seating dies for both.
Re: COAL Acceptable Deviation?
I just loaded up 50 175gr SMK's this morning & they ranged anywhere from 2.229" - 2.2315"(measuring to the ogive).
These were seated with a Redding competition seater & measured with Starrett calipers FWIW.
Don't know how much it's going to matter anyhow since my bullets have to jump roughly .135" to the lands.
I just loaded up 50 175gr SMK's this morning & they ranged anywhere from 2.229" - 2.2315"(measuring to the ogive).
These were seated with a Redding competition seater & measured with Starrett calipers FWIW.
Don't know how much it's going to matter anyhow since my bullets have to jump roughly .135" to the lands.
Re: COAL Acceptable Deviation?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: terrance250</div><div class="ubbcode-body">I just loaded up 50 175gr SMK's this morning & they ranged anywhere from 2.229" - 2.2315"(measuring to the ogive).
These were seated with a Redding competition seater & measured with Starrett calipers FWIW.
Don't know how much it's going to matter anyhow since my bullets have to <span style="font-weight: bold">jump roughly .135"</span> to the lands. </div></div>
If they're jumping ~0.135" what difference is 0.005" going to make? I'd be looking elsewhere (other variables) for accuracy.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: terrance250</div><div class="ubbcode-body">I just loaded up 50 175gr SMK's this morning & they ranged anywhere from 2.229" - 2.2315"(measuring to the ogive).
These were seated with a Redding competition seater & measured with Starrett calipers FWIW.
Don't know how much it's going to matter anyhow since my bullets have to <span style="font-weight: bold">jump roughly .135"</span> to the lands. </div></div>
If they're jumping ~0.135" what difference is 0.005" going to make? I'd be looking elsewhere (other variables) for accuracy.
Re: COAL Acceptable Deviation?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: buffybuster</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: terrance250</div><div class="ubbcode-body">I just loaded up 50 175gr SMK's this morning & they ranged anywhere from 2.229" - 2.2315"(measuring to the ogive).
These were seated with a Redding competition seater & measured with Starrett calipers FWIW.
Don't know how much it's going to matter anyhow since my bullets have to <span style="font-weight: bold">jump roughly .135"</span> to the lands. </div></div>
If they're jumping ~0.135" what difference is 0.005" going to make? I'd be looking elsewhere (other variables) for accuracy. </div></div>
Exactly, that's the point I was trying to make. I'm still in the beggining stages of load development, so accuracy, or lack there of, has yet to be established.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: buffybuster</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: terrance250</div><div class="ubbcode-body">I just loaded up 50 175gr SMK's this morning & they ranged anywhere from 2.229" - 2.2315"(measuring to the ogive).
These were seated with a Redding competition seater & measured with Starrett calipers FWIW.
Don't know how much it's going to matter anyhow since my bullets have to <span style="font-weight: bold">jump roughly .135"</span> to the lands. </div></div>
If they're jumping ~0.135" what difference is 0.005" going to make? I'd be looking elsewhere (other variables) for accuracy. </div></div>
Exactly, that's the point I was trying to make. I'm still in the beggining stages of load development, so accuracy, or lack there of, has yet to be established.
Re: COAL Acceptable Deviation?
I guess I am being to anal about the COAL but we wll see if the new seating dies alleviate most of the problem. 005 I can live with, but some of the 223's 69 gain SMK's were well over that yet the bullets were all within 0.002 of each other.
I guess I am being to anal about the COAL but we wll see if the new seating dies alleviate most of the problem. 005 I can live with, but some of the 223's 69 gain SMK's were well over that yet the bullets were all within 0.002 of each other.
Re: COAL Acceptable Deviation?
This is a great thread. This morning I was measuring some 168 SMK cartridges (unfired obviously) that were left over from a batch I shot yesterday. The COAL was 2.766 to 2.768 and I did notice that at the tip of the hollow points were different in how the bullet fit into the caliper. They were ever so different. I mesured 3 or 4 5 shot groups yetsreday ranging from .3 to .5- nothing really over .5. So I geuss keep on loading!! Only problem is I am almost out of N550 and will have to start a new load with Varget or N150.
This is a great thread. This morning I was measuring some 168 SMK cartridges (unfired obviously) that were left over from a batch I shot yesterday. The COAL was 2.766 to 2.768 and I did notice that at the tip of the hollow points were different in how the bullet fit into the caliper. They were ever so different. I mesured 3 or 4 5 shot groups yetsreday ranging from .3 to .5- nothing really over .5. So I geuss keep on loading!! Only problem is I am almost out of N550 and will have to start a new load with Varget or N150.
Re: COAL Acceptable Deviation?
I measured about 20 of the projos and they varied in length by as much as .006 which supprised me. The COAL varied directly (long or short) with the projo length. Now using Forster Match seating die.
I measured about 20 of the projos and they varied in length by as much as .006 which supprised me. The COAL varied directly (long or short) with the projo length. Now using Forster Match seating die.
Re: COAL Acceptable Deviation?
"What do you guys consider to be acceptable deviation in your preset COAL."
It really doesn't matter what any of us thinks is "acceptable" OAL variation. It's up to your load and your rifle to tell you that. When you find your best load then experiment with seating depth. You will normally find that a range, it's NOT a specfic point. Seat in the middle of that range and the distance either side is YOUR acceptable +/- tolerance, so you don't really care what mine is.
Generally, the bigger the cartridge and/or the bigger the jump, the wider the latitude. But, a spread of 5 thou shouldn't be harmful UNLESS you are seating on a ragged edge of the good range.
"What do you guys consider to be acceptable deviation in your preset COAL."
It really doesn't matter what any of us thinks is "acceptable" OAL variation. It's up to your load and your rifle to tell you that. When you find your best load then experiment with seating depth. You will normally find that a range, it's NOT a specfic point. Seat in the middle of that range and the distance either side is YOUR acceptable +/- tolerance, so you don't really care what mine is.
Generally, the bigger the cartridge and/or the bigger the jump, the wider the latitude. But, a spread of 5 thou shouldn't be harmful UNLESS you are seating on a ragged edge of the good range.
Re: COAL Acceptable Deviation?
I just took out my calipers and measured half a dozen nosler 168's, they are within 5 thousandths of one another. Same for 175 SMK's.
I just took out my calipers and measured half a dozen nosler 168's, they are within 5 thousandths of one another. Same for 175 SMK's.
Re: COAL Acceptable Deviation?
IF your COAL is "walking" most of the time that is a neck-tension issue. As in hardness/thickness etc.
Respectfully,
LG
IF your COAL is "walking" most of the time that is a neck-tension issue. As in hardness/thickness etc.
Respectfully,
LG
Re: COAL Acceptable Deviation?
I usually can expect 0.001"-0.0015" variance using a Hornady seating die with a Microjust Stem and the special 208 AMax seater stem. But, as a rule I never load to "just touching the lands". I either jam 0.010" or step back 0.010". That way if I do have some more variance in OAL, I don't have a situation where some bullets are in the lands and some are just off.
In my experience I have to make seating depth changes of 0.020-0.030" to see a change in the accuracy node. If you are not right at the edge of a sweet spot, 0.005" shouldn't matter in the least.
Chops
I usually can expect 0.001"-0.0015" variance using a Hornady seating die with a Microjust Stem and the special 208 AMax seater stem. But, as a rule I never load to "just touching the lands". I either jam 0.010" or step back 0.010". That way if I do have some more variance in OAL, I don't have a situation where some bullets are in the lands and some are just off.
In my experience I have to make seating depth changes of 0.020-0.030" to see a change in the accuracy node. If you are not right at the edge of a sweet spot, 0.005" shouldn't matter in the least.
Chops
