Inconsistent seating depth .308

[ashley_betts70]

Hi All,
I've just started my first reload of .308 and for some reason I'm getting an inconsistent seating depth. I've just done a run of 5 and the results were 70.52,70.52,70.44,70.40,70.48mm. I'm aiming for 70.48. The die seems to be set ok (i.e. not loose or moving). I'm using Sierra 155g HPBT. Is this to be expected? From min to Max that's about 5 thou.

Also, on slightly different point, I've used 43g of AR2206H. That fills the cartridge to the neck. I was going to progress the loads in whole grain increments from 43 to 46 but I'm now a bit nervous my load density is too high. I can hear a slight rattle of powder at 43g so there must be a little room. Is it normal for loads to have powder encroaching into the neck?

Regards,

Ashley

[5Tom]

As long as your loads are within the safety margins illistrated by your chosen manual, you should be ok. Personally I think having powder fill up the neck won't leave too much room for the projectile to seat properly, which could be your issue.

You might need to check your sizing die incase the projectile isn't being seated tight enough as so it could be pushed in further if slightly bumped. Which reloading manual are you using?

[Baldrick314]

Hi All,
I've just started my first reload of .308 and for some reason I'm getting an inconsistent seating depth. I've just done a run of 5 and the results were 70.52,70.52,70.44,70.40,70.48mm. I'm aiming for 70.48. The die seems to be set ok (i.e. not loose or moving). I'm using Sierra 155g HPBT. Is this to be expected? From min to Max that's about 5 thou.

Also, on slightly different point, I've used 43g of AR2206H. That fills the cartridge to the neck. I was going to progress the loads in whole grain increments from 43 to 46 but I'm now a bit nervous my load density is too high. I can hear a slight rattle of powder at 43g so there must be a little room. Is it normal for loads to have powder encroaching into the neck?

Regards,

Ashley

What dies are you using? I've found with some dies it helps to just back the seating depth adjustment back a touch betweens seating bullets and then wind down again to get consistent results. Also for overall length I'd advise using inches as a unit of measurement not mm. Thousands of an inch are smaller so allow a more precise measurement.

43gr of 2206h seems like quite a lot for a starting load. I use 42gr and on warm days that will give me slight pressure signs. When I developed that load I started at 39gr and worked up. Also when working up a load you should go up in half grains not full grains.

[ashley_betts70]

What dies are you using? I've found with some dies it helps to just back the seating depth adjustment back a touch betweens seating bullets and then wind down again to get consistent results. Also for overall length I'd advise using inches as a unit of measurement not mm. Thousands of an inch are smaller so allow a more precise measurement.

43gr of 2206h seems like quite a lot for a starting load. I use 42gr and on warm days that will give me slight pressure signs. When I developed that load I started at 39gr and worked up. Also when working up a load you should go up in half grains not full grains.

Hi Baldrick,
Thanks for the response. The dies are lee (deluxe set). I'll try the method you explained. On the measurement side, my dial callipers are metric with a measurement increment of 0.02mm. That's actually less than a thou of an inch (0.001" = 0.0254mm).

I got the load data from the ADI hand loading guide and also reconfirmed with the load data on their website. 43g start load for 155g bullet, max 46g. I just charged 10 shells with 44g and I don't like the look of it from a load density point of view. Even after a few taps on the bench the powder is into the neck. The brass is lapua palma.

[Techc]

Also, on slightly different point, I've used 43g of AR2206H. That fills the cartridge to the neck. I was going to progress the loads in whole grain increments from 43 to 46 but I'm now a bit nervous my load density is too high. I can hear a slight rattle of powder at 43g so there must be a little room. Is it normal for loads to have powder encroaching into the neck?

Yeah, that's normal.

Depending on the load and powder it can be anywhere from below the neck where you can shake it and hear the powder like a little maraca, to well into the neck and slightly compressed by the bullet with no room for movement.

Double check everything as usual, but 43gr - 46gr of 2206H and 155gr pills is correct.

[ashley_betts70]

Yeah, that's normal.

Depending on the load and powder it can be anywhere from below the neck where you can shake it and hear the powder like a little maraca, to well into the neck and slightly compressed by the bullet with no room for movement.

Double check everything as usual, but 43gr - 46gr of 2206H and 155gr pills is correct.

Thanks Techc, I've been reloading 44-40 which, even with max loads, looks like you have enough room to stuff a small animal into it before seating a bullet. The first load charge of the 308 looked very cosy for the projectile. The maraca sound confirms there is some space however. Been an awful long time since I reloaded rifle cartridges.

[Baldrick314]

What dies are you using? I've found with some dies it helps to just back the seating depth adjustment back a touch betweens seating bullets and then wind down again to get consistent results. Also for overall length I'd advise using inches as a unit of measurement not mm. Thousands of an inch are smaller so allow a more precise measurement.

43gr of 2206h seems like quite a lot for a starting load. I use 42gr and on warm days that will give me slight pressure signs. When I developed that load I started at 39gr and worked up. Also when working up a load you should go up in half grains not full grains.

Hi Baldrick,
Thanks for the response. The dies are lee (deluxe set). I'll try the method you explained. On the measurement side, my dial callipers are metric with a measurement increment of 0.02mm. That's actually less than a thou of an inch (0.001" = 0.0254mm).

I got the load data from the ADI hand loading guide and also reconfirmed with the load data on their website. 43g start load for 155g bullet, max 46g. I just charged 10 shells with 44g and I don't like the look of it from a load density point of view. Even after a few taps on the bench the powder is into the neck. The brass is lapua palma.

Ahh missed the part about 155gr projectiles. I'm using 168. That explains the difference in powder weights.

[Deco]

Thanks Techc, I've been reloading 44-40 which, even with max loads, looks like you have enough room to stuff a small animal into it before seating a bullet. The first load charge of the 308 looked very cosy for the projectile.

A mate of mine loads .300 Win Mag... The powder is full to the brim.

[reddog]

Just thinking from memory but isnt Palma match brass slightly smaller than standard .308 ?

[Norton]

Just thinking from memory but isnt Palma match brass slightly smaller than standard .308 ?

Small primer pocket and using small rifle primers instead of large isn't it?

But the brass is otherwise the same?

I think...