7mm08 Seating Depth

[thomas89]

Groups from the other day, OACL of 2.85 on the left, and 2.80 on the right. Recommended OACL from Barnes is 2.800.

From that same 20” 7mm08 flaky Howa.

Other than that monster flyer, I think the group from the 2.85 load shot best, with no pressure signs, but I can’t decide should I fiddle with this more or am I chasing my tail? I don’t have a surplus of primers that I want to tie up with this, and I am using a hand press to load these so playing with .001’s of an inch seating depth is frustrating to say the least.

 

[Addicting]

Barnes recommends .030 difference in seating depth when testing. .005 is a waste of time and resources, especially with those groups.

Actually move it and you should see them tighten up.

 

[p_ham]

Barnes recommends .030 difference in seating depth when testing. .005 is a waste of time and resources, especially with those groups.

Actually move it and you should see them tighten up.

2.8 and 2.85 is a .05 jump...just sayin

@thomas89 I would start at mag length (assuming you have enough jump to the lands, at least .05) and work my way shorter .03" at a time as @Addicting mentioned.
Unless you did something crazy on that flyer I wouldn't trust that load.

 

[JLS]

I don’t really pay much attention to OACL. Find your lands. Go 0.050” off and try that.

What bullet and powder combo?

 

[Addicting]

2.8 and 2.85 is a .05 jump...just sayin

@thomas89 I would start at mag length (assuming you have enough jump to the lands, at least .05) and work my way shorter .03" at a time as @Addicting mentioned.
Unless you did something crazy on that flyer I wouldn't trust that load.

Totally missed that with his comment of .001. My bad, that’s what I get for posting when I’m working.

 

[thomas89]

I don’t really pay much attention to OACL. Find your lands. Go 0.050” off and try that.

What bullet and powder combo?

140gr TTSX and Varget. Don’t have any other powder or bullets I’d want to work with.

It’s all just for fun anyhow.

October 1 is my elk opener so I’d like to have it sorted out by then.

 

[JLS]

140gr TTSX and Varget. Don’t have any other powder or bullets I’d want to work with.

It’s all just for fun anyhow.

October 1 is my elk opener so I’d like to have it sorted out by then.

Magnum primer or regular? If regular, try a magnum primer and seat deeper.

I’ve never found Barnes to like being close to the lands.

 

[std7mag]

With Varget i don't thing they need to worry about a magnum primer. Should ignite fine with a standard primer.

@thomas89
You need to read the rest of the manual.
The 2.800" is SAAMI length for the 7mm-08. Just so you can load anyones ammo in any 7mm-08 chamber.

As for COAL, your probably going to be more realistically in the 2.780" or less range.

Find your lands & go 0.050" less.

 

[G. McAlister]

Both my Howas won’t chamber a 140 grain TTSX longer than 2.795” COAL. Shoots pretty well though, so I don’t complain. Still annoying to look at all the cartridges that fit in a Ruger American chamber I no longer own.

 

[AussieIves]

I struggle to achieve extreme tight coal tolerances with a manual press. I loaded up some 162gr eldx at 2.875” and got a decent group. The Barnes TTSX 150gr I loaded to the recommended 2.775” and couldn’t get a decent group. Might be many other factors but gee they looked short in the magazine

 

[ImBillT]

I don’t know anything about Howas, but a 700 S/A will only fit a hair over 2.800” in the magazine.

There’s no need to fine tune seating depth until most of your groups are one hole groups. Rough seating depth testing should be to load groups of 6-10 rounds with .020”-.040” between each groups, and covering a span of at least .120”. Shoot 3 or 5 shot groups with each seating depth. One should stand out. Repeat. If the same seating depth stands out, you’ve found something. If not, either the bullet is insensitive to seating depth and you have a lot of good groups, or something else is a major problem and you’re wasting your time.

 

[std7mag]

I struggle to achieve extreme tight coal tolerances with a manual press. I loaded up some 162gr eldx at 2.875” and got a decent group. The Barnes TTSX 150gr I loaded to the recommended 2.775” and couldn’t get a decent group. Might be many other factors but gee they looked short in the magazine

Your co.paring apples to the horse pulling the cart!

Unless your charge is really compressed, i don't see where you would have a problem maintaing COAL.

 

[p_ham]

Your co.paring apples to the horse pulling the cart!

Unless your charge is really compressed, i don't see where you would have a problem maintaing COAL.

Ive seen it if the seating stem doesn't fit the ogive and the point hits it. Even then it's only a few thou.
At any rate, of course the COAL is going to be different with different bullets!!

 

[wyoelkhunter17]

Check with bullet seating tool then back off roughly .030 and move from there. If internal mag check clearance on that and adjust from there

 

[Don Fischer]

I think a big problem many shooter's have is they are actually hunter's looking for match accuracy from hunting rifles! It's a head game we play with ourselves. I figure all my rifles should do 1" or better at 100yds and most do but I've never had a shot other than with a varmint rifle where I needed that kind of accuracy. I have it stuck in my head that the bullet needs to be just of the lands to shoot best. Don't ask what just off the lands is as I haven't a clue! What I do have is a few rifles that if I do my part they will go 1/2" at 100 yds.