Here we go a can of worms. But as many know it really makes a difference in accuracy.
Interesting video I have watched a couple years ago.
Interesting video I have watched a couple years ago.
I used this video when I did load development on my 6.5 using VLD's. I found a charge at 40.9 grains of H4350 that made decent SD's and used it. Started at .030" from jam and worked back. I had to start at .030" to fit in my mag. I ended up grooving out my feed ramp (HMR Pro's have this, HMR's do not) to get them to feed reliability. Found a pretty wide node and was stoked.
Yes I have Hornady Zombie Max 55gr .223 I took my inertia puller and made them longer and then seated them to where my .223 liked them.
Accuracy came way up but that also removed any crimp that Hornady gave them.
I did a factory ammo test and shot 5 and then removed the components and measured everything and slicked up the necks and stuck them back together and shot better groups with them.
Hornady was the worst and I figured those bullets may want to be longer.
Tulammo was best.
Tulammo was the best?
I think this video has some poor advice.
First off, finding your lands by jamming a dummy cartridge doesn't work well and can give false results. The bullet is being pressed into the lands, and as he admits, risks pulling out of the case a bit on extraction. This can give a false, excessively long measurement. I used to struggle with this method in various forms (tight neck, loose neck, split neck, etc). I had difficulty getting consistent results. When I found out that one of my (supposed) 0.010" seating depth loads was actually jamming bullets I finally bought the proper tools. You need a Hornady bullet seating depth gauge and a fired case modified by Hornady (or a machine shop) to thread on to the gauge. No exception. It only takes a few minutes to use it and the results are consistent.
He makes the point that seating depth is a safety issue. He says distance to lands doesn't matter. Then he goes and attempts to find the distance to land and sets his seating depth for his load. I thought that "didn't matter"? Then he makes assumptions about his throat wear based off accuracy results. And he's going to keep seating the bullet further out, chasing the group. Is he going to recheck his land measurement at some point or does he really not care anymore? The load I mentioned where I was jamming my bullets due to a bad measurement was my most accurate load. If I followed his advise, I'd still be chasing the jam!
I seat 0.010" off the lands to start combined with collect neck sized cases separated by neck runout. I then work up the powder load until I hit a sweet spot. I recheck distance to lands occasionally as a safety check or when changing bullets.
First off, finding your lands by jamming a dummy cartridge doesn't work well and can give false results. The bullet is being pressed into the lands, and as he admits, risks pulling out of the case a bit on extraction. This can give a false, excessively long measurement. I used to struggle with this method in various forms (tight neck, loose neck, split neck, etc). I had difficulty getting consistent results. When I found out that one of my (supposed) 0.010" seating depth loads was actually jamming bullets I finally bought the proper tools. You need a Hornady bullet seating depth gauge and a fired case modified by Hornady (or a machine shop) to thread on to the gauge. No exception. It only takes a few minutes to use it and the results are consistent.
He makes the point that seating depth is a safety issue. He says distance to lands doesn't matter. Then he goes and attempts to find the distance to land and sets his seating depth for his load. I thought that "didn't matter"? Then he makes assumptions about his throat wear based off accuracy results. And he's going to keep seating the bullet further out, chasing the group. Is he going to recheck his land measurement at some point or does he really not care anymore? The load I mentioned where I was jamming my bullets due to a bad measurement was my most accurate load. If I followed his advise, I'd still be chasing the jam!
I seat 0.010" off the lands to start combined with collect neck sized cases separated by neck runout. I then work up the powder load until I hit a sweet spot. I recheck distance to lands occasionally as a safety check or when changing bullets.
I found out last night that if I switch to an Aluminum magazine for my Ruger Precision Rifle I can seat my bullets less and get closer to the lands than the PMAG allows me to be.
I am tempted to work on that..
I am tempted to work on that..
I single seated some .223 bolt gun ammo 2.278" into my ar and it tightened the groups a lot.
Another ar of my buddies will not close with that ammo.
Ya never know until you try.
Another ar of my buddies will not close with that ammo.
Ya never know until you try.
I use blue Loctite when I seat a dummy round to find the lands. Plus, it will come off the inside of the case neck if you clean in stainless steel media.
