• Help Support TNDeer:

Micrometer seater die set on sale

Seating depth can make a WORLD of difference.... Back several years ago, I worked up a load for my .243 TC Encore barrel that was giving me very consistent FPS, but the groups were still an inch or so at 100yds. Most of my bullet seating dies are the fancy micrometer type from RCBS, so I decided to experiment with the seating depth a little, and made up 3 rounds each from .000 off the lands, .002, .003, all the way down to .020... During range day, I recorded everything as I shot and found that when I fired the 3 rounds that were .006 from the lands, Whoop! The group shrank down to a cloverleaf. Every other load stayed at around 1 inch. I've since shot many groups with that load that a dime would cover. I'm a big believer in seating depth importance!

I wish FA had made (or that I knew about) that set before I'd bought so many micrometer seater dies from RCBS!
 
Last edited:
utvolsfan77 said:
When you set depth close to rifling, did you experience major pressure spikes? Looking to adjust seating depth on several of my favorite rifles.
Click to expand...
That is a common occurrence when "jamming" the bullet into the lands. On the initial firing from the primer, the powder ignites, and the bullet is actually plugged and can't move without significant force to get it started into the lands. Giving it a jump helps alleviate this issue, and also helps tune for accuracy. That said, some bullet/rifle combinations just work best with the bullet jammed into the lands. Test test test. :)
 
utvolsfan77 said:
When you set depth close to rifling, did you experience major pressure spikes? Looking to adjust seating depth on several of my favorite rifles.
Click to expand...
The starting depth of .000 was where the bullet would just barely touch the lands, and it didn't take any extra effort to close the gun. I have one of those plastic and metal "adjustable" fake bullets that let's you find the exact length of your chamber so you can set up the bullet seater die to know just what you're dealing with when it comes to seating depth.

I didn't notice any over-pressure signs on any of my rounds while testing seating depth. That's not to say it wouldn't on another load or barrel, but in this case, everything went very smoothly. YMMV.

I had already done a LOT of testing with that barrel before I settled on the final load. I think I went thru about 8 or 9 different powders, probably the same number of different bullets. I was at around 1500 rounds or more by the time I decided which load I liked the best.. The seating depth was just the icing on the cake.

Now I need to do the same thing with my 6.5 CM barrel...
 

Latest posts

Back
Top