Bullet seating depth Q

In regards to the original question, if you're checking on a bolt action with a easily removable bolt, this is quite easily done. Insert bolt and close, insert rod (close to bore diameter works best) from muzzle end until it touches the bolt face. Mark at muzzle. Remove bolt, and pull you measuring rod back. Insert the bullet you wish to use into the chamber, pushing it all the way forward to rest against the lands with another rod or dowel. Slide your original rod in to touch the bullet, and mark it at the muzzle. Measure between your two marks (a small machinist rule works well for this) and that is your max coal for that cartridge and that bullet. I have used a stoney point before as well, the end result was almost identical. I would repeat with at least 3 bullets in that lot to give a statistically relevant measurement. FWIW. - dan
 
It goes like this.
https://bulletin.accurateshooter.co...lenn-kulzer-sets-8-1000-yard-records-in-2021/
Glen’s mentor, Tom Mousel, chronographs everything and it’s NEVER low Sd or Es.
Glen is shaving tenths at 1k jamming with .005 neck tension. Tom has been up to .008 neck tension in testing.
Jumping will shoot 95% as good as jamming hard. Seat your bullets .001 with your bolt to find a baseline comparison to jumping/mag feeding. With slightly reduced powder charge of course.
Alex Wheeler smith’s for them. He built a new gun a week before a match at Deep Creek Montana and shot five shot groups on Saturday and Sunday measuring 1.5xx inches at 1000 yards. Piling up data is a fools errand.
I’ve followed Tom since 2013 and can get a new custom barrel into the same hole in two dozen rounds. That’s common among those that tune off the target.
Now if your POA is changing under recoil and torque any changes will be lost in the fog of shooter error. That’s why Hornady, Modern Day Sniper and the like preach 1MOA is all you can expect.
There’s a $5 Billion/year global firearms accessory industry that’s funded by UNACCOUNTED SHOOTER ERROR.
 
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Why not use Sierra 2156? Seating depth is "Jam It", Look at the primers, prefer to use small primer brass. 3000 fps is okay but don't gp much over. Where are you located? If you jam them you must be able to unload in case of a cease fire and not leave bullet and powder in the chamber.
 
I used 2155's with 46.0 gr of Varget in Lapua brass. I can't get as close to the lands as my best results show, unless I single load. They won't feed from my plastic AICS mag at my ideal length.
 
Ian Robertson said:
Why not use Sierra 2156? Seating depth is "Jam It", Look at the primers, prefer to use small primer brass. 3000 fps is okay but don't gp much over. Where are you located? If you jam them you must be able to unload in case of a cease fire and not leave bullet and powder in the chamber.
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I still have couple old boxes of 2155 I want to empty first @ 300 before jumping to 2156 @ 500 and beyond.
This how I was planning it back in time, but the prone shooting is put on hold for medical reasons, for now.... a real pita ...
So far the 45.8 gn Varget with 0.026" seating depth @ AV 2989 fps was the last good working setup from a time before the summer heat hit us. Tinkering I may go lower with powder for 0.1 or 0.2 gn.
I got my new - slip on barrel tuner yesterday, the plan was to do a batch of amo and test it out again from a bench, probably for a weekend. I just checked and looks like I will be short on Varget for this workparty.
 
Around and around and around we go.
You found a load that works well, by playing around with powder charges and seating depths. Now you are going to clamp on a barrel tuner that by just installing it, will change the harmonics of the barrel. Very likely change the point of impact and mat open up the groups. Now you will play with the barrel tuner to get the load to shoot just as well as the load you have already have without the tuner.

If your rifle and load are .5MOA or better it is good enough. The matches are won and lost by the best wind reader pulling the trigger. You can't buy points.
 
dan belisle said:
In regards to the original question, if you're checking on a bolt action with a easily removable bolt, this is quite easily done. Insert bolt and close, insert rod (close to bore diameter works best) from muzzle end until it touches the bolt face. Mark at muzzle. Remove bolt, and pull you measuring rod back. Insert the bullet you wish to use into the chamber, pushing it all the way forward to rest against the lands with another rod or dowel. Slide your original rod in to touch the bullet, and mark it at the muzzle. Measure between your two marks (a small machinist rule works well for this) and that is your max coal for that cartridge and that bullet. I have used a stoney point before as well, the end result was almost identical. I would repeat with at least 3 bullets in that lot to give a statistically relevant measurement. FWIW. - dan
Click to expand...
I think this method is the best and is more accurate than "long" seating a bullet in a case and feeling it while closing the bolt... leave the bolt cocked or remove the firing pin when measuring so the firing pin tip isn't interfering.
 
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maynard said:
Around and around and around we go.
....
If your rifle and load are .5MOA or better it is good enough. The matches are won and lost by the best wind reader pulling the trigger. You can't buy points.
Click to expand...
:) Aren't we all in a same rabbit hole chasing the very last 5%
 
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