quote:

Originally posted by miles58:
Saeed,

I have solved 50 rifles give or take a dozen or so for monos. Most of them were Barnes. Calibers from 22 to 45 (50 caliber muzzle loaders.

Some, were flat out easy and had absolutely no seating depth issues. The muzzle loaders having neither cartridges nor throats not any capability whatsoever to have a "seating depth" uniformly shot accurately and did so independently for the most part of their velocity.

Common cartridge rifles could require not only a specific seating depth, but also a very small tolerance for variance of seating depth. One .223 Remington, a Savage 12 with a 26 inch barrel. would shoot 8 inch groups at any more or less than .005 inches from it's preferred depth and well under an inch when on the money.

Some rifles just didn't care about seating depth. I would guess that maybe between 4 and 10 fell into that category. Most rifles would shoot 2-3 inches when the hit the pressure level they like and then drop in under an inch when I found the right seating depth. Preferred seating depth varied from a hard jam into the lands to well over .100 off the lands.

Rifle make and model showed no group preference. One Remington 700 in 30-06 might like .010 off and the next might like .075. Of my 700s in .270 Variance in seating depth preference is as variable as preference for one powder or another.

I did not find a give powder in a given rifle changed the rifle's preference for seating depth for a given bullet. ie: my 25-06 shooting 100 grain TSXs needed the same seating depth regardless of powder and it retained that opinion with factory ammo loaded with the same bullet.

The rifles I tried both TSX and TTSX bullets of the same weight in had different preferences for seating depth and the accuracy they produced.

I used both seating depth and distance to lands in this recitation. In all cases I measured seating distance to the lands with a Stoney Point gauge. Getting a good CONSISTENT measurement is not easy and makes for more tedious load development, but I strongly believe that it is necessary. Once the distance the rifle likes the bullet to be off the lands is established and the press is locked down tight, a few boxes being loaded generally will not produce enough variance due to press and bullet variation to affect accuracy noticeably.

The bullets I loaded were Barnes Hornady and Nosler only. The Barnes were probably the easiest to do load development for with the Hornady and Noslers being about equally more PITA, but usable and like the Barnes showing a preference for distance to lands and some rifles preferring them and some the Barnes.

The Barnes copper varmint bullets are a cup and core variation with copper shot in a jacket and thus performed more like a jacketed lead bullet.

I had one rifle that flat out refused to give me under an inch at velocity near the to of that cartridge's potential, but woud produce accuracy at starting load level. I had one rifle that had a very nice looking bore and shot Hornady jacketed lead bullets quite nicely but 3 shots with a Barnes of the same weight was sufficient to foul it badly enough that it was shooting groups of several inches. That rifle after treatment with Dyna Bore Coat quit fouling badly and would shoot extended strings of Barnes with acceptable accuracy.[FLASH_VIDEO] [/FLASH_VIDEO]

quote:

Originally posted by Saeed:
As a rule, I load all my ammo to the maximum OAL for that cartridge.

If the bullets are short, I load a minimum of one caliber in the case neck.

I have never even tried different seating depths, except for my test.

And in that I found very little difference.

quote:

Before I have hunted with a 416 Weatherby Magnum, loaded with 105 grains of powder.

So I thought I would try the same load.

I fired 3 Trophy Bonded Bear Claws.

They made one ragged hole.

I took the same cases, resized them and loaded them with Barnes Super Solids brass bullets.

Fired them at the same target.

All 6 went into around 0.7".

That was the only load development I did for that rifle.

quote:

Originally posted by miles58:

quote:

Originally posted by miles58:
Saeed,

I have solved 50 rifles give or take a dozen or so for monos. Most of them were Barnes. Calibers from 22 to 45 (50 caliber muzzle loaders.

Some, were flat out easy and had absolutely no seating depth issues. The muzzle loaders having neither cartridges nor throats not any capability whatsoever to have a "seating depth" uniformly shot accurately and did so independently for the most part of their velocity.

Common cartridge rifles could require not only a specific seating depth, but also a very small tolerance for variance of seating depth. One .223 Remington, a Savage 12 with a 26 inch barrel. would shoot 8 inch groups at any more or less than .005 inches from it's preferred depth and well under an inch when on the money.

Some rifles just didn't care about seating depth. I would guess that maybe between 4 and 10 fell into that category. Most rifles would shoot 2-3 inches when the hit the pressure level they like and then drop in under an inch when I found the right seating depth. Preferred seating depth varied from a hard jam into the lands to well over .100 off the lands.

Rifle make and model showed no group preference. One Remington 700 in 30-06 might like .010 off and the next might like .075. Of my 700s in .270 Variance in seating depth preference is as variable as preference for one powder or another.

I did not find a give powder in a given rifle changed the rifle's preference for seating depth for a given bullet. ie: my 25-06 shooting 100 grain TSXs needed the same seating depth regardless of powder and it retained that opinion with factory ammo loaded with the same bullet.

The rifles I tried both TSX and TTSX bullets of the same weight in had different preferences for seating depth and the accuracy they produced.

I used both seating depth and distance to lands in this recitation. In all cases I measured seating distance to the lands with a Stoney Point gauge. Getting a good CONSISTENT measurement is not easy and makes for more tedious load development, but I strongly believe that it is necessary. Once the distance the rifle likes the bullet to be off the lands is established and the press is locked down tight, a few boxes being loaded generally will not produce enough variance due to press and bullet variation to affect accuracy noticeably.

The bullets I loaded were Barnes Hornady and Nosler only. The Barnes were probably the easiest to do load development for with the Hornady and Noslers being about equally more PITA, but usable and like the Barnes showing a preference for distance to lands and some rifles preferring them and some the Barnes.

The Barnes copper varmint bullets are a cup and core variation with copper shot in a jacket and thus performed more like a jacketed lead bullet.

I had one rifle that flat out refused to give me under an inch at velocity near the to of that cartridge's potential, but would produce accuracy at starting load level. I had one rifle that had a very nice looking bore and shot Hornady jacketed lead bullets quite nicely but 3 shots with a Barnes of the same weight was sufficient to foul it badly enough that it was shooting groups of several inches. That rifle after treatment with Dyna Bore Coat quit fouling badly and would shoot extended strings of Barnes with acceptable accuracy.

Oops Edited to add recommendations on changes

I will usually start at Barnes 4 manual seating depth or .050 off. If that does not produce sub inch accuracy theI move up to .010 0ff and if I see notable improvement I will normally move up to bump the lands. If that does not work then starting at .020 off I just methodically move back in .010 increments. Not a lot of fun, but over the long haul it saves on bullets that are somtimes hard to come by.