help with redding competition seater & 175gn smk's

[elfster1234]

New to reloading here. Using redding competition seating die with hornady LNL AP press. Reloading for my 7.62 nato chamber LMT, with .308 once fired federal brass, some once fired 7.62 military brass, and sierra smk hpbt 175grn bullets. I'm getting around a .010 veriance between seatings. I'm trying to get a perfect 2.800 coal as per sierra's specs and they fit in my pmag. I need to consistant back off .015 after each seating and dial down. Damn near every seating is different varience. I've checked my factory HPBT 7.62 american eagle ammo and they are all damn near 2.800 and vary on the factory ammo a little bit on COAL +/-. I can do the same 2.800, but I need to back off the micro dial .015 on every round and run them thru atleast 2 to 3 times and dial down every time. Is this normal? Is it the die? is it the sierra's ogive? what is the deal? is this something i need to expect if i want a perfect 2.800 on each of my bullets... I mean, i can do a perfect 2.800 on each one but i need to run them thru 2 to 3 times while dialing down the seater.

I've made a dummy round with no powder / primer,,,, and can run the dummy off the magazine, into the chamber, and eject just fine like factory ammo.

I was just hopying I could use a nice bullet, set my seater, and forget it and get atleast close to 2.800 without backing off .015 and dialing down each bullet to get a perfect 2.800... Maybe i'm just being to much of a perfectionts?

Any help would be great.

 

[tipper]

Re: help with redding competition seater & 175gn smk's

You need this.

Hornady Lock-N-Load Bullet Comparator Basic Set with 6 Inserts

The Hornady Lock-N-Load Bullet Comparator is perfect for the reloader looking to quickly and precisely measure seating depth of loaded ammunition from the bullet ogive to the base of the loaded round, to eliminate variation in seating depth. The comparator attaches to any caliper and measures cartridges from 17 to 45 caliber. When used in conjunction with the Hornady Lock-N-Load Overall Length Gage (Sold Separately) you will able to determine the exact bullet seating depth for the ultimate precision.

http://www.midwayusa.com/product/231904/...-with-6-inserts

 

[ltfirehunter]

Re: help with redding competition seater & 175gn smk's

You need to measure at the ogive not the bullet tip, plus you will get consistent jump to the lands. You will have variance in oal length due to where the seater contacts the bullet with the seater.

 

[memilanuk]

Re: help with redding competition seater & 175gn smk's

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ltfirehunter</div><div class="ubbcode-body">... will have variance in oal length due to where the seater contacts the bullet with the seater.</div></div>

While that does exist, its relatively minimal (in my experience) compared to the inherent variance in the OAL of the bullet itself resulting from the forming process.

Its not unheard of for SMKs to vary 20 or even 30 thou within a batch.

If you're seating to 2.800" for magazine length, I presume thats because the mag will accept 2.810 or 2.820" (maybe even 2.850"). Treat that 2.800" as an average, call it good, and get on with loading. It is a number pulled out of a hat, for feeding/reliability reasons, not for precision reloading reasons. No need to obsess over it.

If you want to seat relative to the lands, i.e. +5 thou jam or -20 thou jump, rather than a arbitrary fixed OAL... then get the Hornady LnL tools mentioned earlier, measure, set and load away.

 

[DamnYuppie]

Re: help with redding competition seater & 175gn smk's

Even after measuring off the ogive you will have to reset the depth for each batch of bullets. I have found that between boxes of 175's there can be as much a .015 difference. That is why it is a good idea to buy them in boxes of 500 or more.

 

[elfster1234]

Re: help with redding competition seater & 175gn smk's

yeah, my 2.800 just makes the pmag...i'm thinking anything over 2.820 wouldn't fit the pmag. The american eagle 7.62x51 HPBT factory ammo I usually shoot is all mostly set at 2.800 coal and runs great in my rifle. I'll need to look into that bullet comparitor set tho. I think it would still be nice to know and might do a batch base totally off ogive just as the coal doesn't push 2.800 so they fit into my magazine...??..?? or am I wasting my time???. I think going off 2.800 coal for my LMT's semi auto pmag would be ok???,,,, but I do have a friend with a bolt action that would like to reload also in which i'm sure we would really need to get a bullet comparitor as he has tons of room with his magazine and would be base more off ogive / lands and not COAL correct?? which would hopefully make seating bullets more accurate and would help speed up the reloading process.

Thanks to everyone for your info. This helps out a bunch.

Do some of you sort out your bullets by length / ogive / weight also?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: memilanuk</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ltfirehunter</div><div class="ubbcode-body">... will have variance in oal length due to where the seater contacts the bullet with the seater.</div></div>

While that does exist, its relatively minimal (in my experience) compared to the inherent variance in the OAL of the bullet itself resulting from the forming process.

Its not unheard of for SMKs to vary 20 or even 30 thou within a batch.

If you're seating to 2.800" for magazine length, I presume thats because the mag will accept 2.810 or 2.820" (maybe even 2.850"). Treat that 2.800" as an average, call it good, and get on with loading. It is a number pulled out of a hat, for feeding/reliability reasons, not for precision reloading reasons. No need to obsess over it.

If you want to seat relative to the lands, i.e. +5 thou jam or -20 thou jump, rather than a arbitrary fixed OAL... then get the Hornady LnL tools mentioned earlier, measure, set and load away. </div></div>

 

[elfster1234]

Re: help with redding competition seater & 175gn smk's

thanks, this is good info.. is there any other bullets that compare in accuracy that doesn't have such a huge difference in ogive measurements?

thanks a bunch and i'm learning a bunch here. starting to get a solid idea on this stuff.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DamnYuppie</div><div class="ubbcode-body">Even after measuring off the ogive you will have to reset the depth for each batch of bullets. I have found that between boxes of 175's there can be as much a .015 difference. That is why it is a good idea to buy them in boxes of 500 or more. </div></div>

 

[memilanuk]

Re: help with redding competition seater & 175gn smk's

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">we would really need to get a bullet comparitor as he has tons of room with his magazine and would be base more off ogive / lands and not COAL correct?? </div></div>

Depends... Remington with factory mags... probably not. I think max OAL in a mag on the 700VS I used to have was something like 2.825", but the throat was so long as to make Roy Weatherby proud... by way of contrast, several of the Savage rifles I have come with fairly long mags - max OAL is somewhere over 2.950", so I can generally seat relative to the lands easily enough - until, that is, I 'upgraded' to an AI-pattern magazine system. Guess what - the max OAL is more oriented for a Remington (or just SAAMI spec) so I'm back to 'short' rounds again.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Do some of you sort out your bullets by length / ogive / weight also? </div></div>

I do... but not for my tactical rifles, or anything really short of my 'match' F-Class rifles. I approach that stuff pretty seriously... but if you're still loading to mag length and your friend is just getting into it... it's close to the last thing on the list you need to worry about.

As for the bullet options... to be honest, I have never seen *that* much variance in ogive measurements (15 thou) in any lot of any make. Then again, I've been told that I've been very, very fortunate in that regard <shrug>. Hornady might b another option with their 178 A-Max and HPBT, or Berger with their 175gn OTM (be prepared for sticker shock, though).

 

[Jackalope33B]

Re: help with redding competition seater & 175gn smk's

What I have done is bullet sort all my 175SMK's. I have noticed a constant variance of about .012. There are usually 3 separate bullet variances within a batch of 100 bullets from what I have noticed. Separate your bullets into different piles, load from one pile of bullets and your OGIVE depth will be within .002, not bad IMO. When you switch to a different pile, you will only have to adjust your DIE a few thousdanths and load awayyyyyyyyy!

THe hornady bullet comparator is a must! I use that to sort my bullets.

 

[elfster1234]

Re: help with redding competition seater & 175gn smk's

this is what i had in mind for my friend's bolt action... good info. thank you!

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jackalope33B</div><div class="ubbcode-body">What I have done is bullet sort all my 175SMK's. I have noticed a constant variance of about .012. There are usually 3 separate bullet variances within a batch of 100 bullets from what I have noticed. Separate your bullets into different piles, load from one pile of bullets and your OGIVE depth will be within .002, not bad IMO. When you switch to a different pile, you will only have to adjust your DIE a few thousdanths and load awayyyyyyyyy!

THe hornady bullet comparator is a must! I use that to sort my bullets. </div></div>