TUBBS DTAC 115 GR. - SEAT DEPTH

[Bill Norris]

Thought I would pass on a little info I have found with the DTACs. It has been said in various places online that the DTACs wanted to shoot @ .010 - .020 off the lands. When I first started messing around with it in a shooting buddies 6XC I saw that if I got any closer than .007 to the lands it did not want to group. I then tried some loads in my 243AI and again found it wanted to be at .010 or more away from the lands in order to group well. Just recently I started working with it in my new ODCR 6BRX and have again found that it wants to be at .020 off the lands to group well. It will shoot decent closer to the lands but in order to stay down in the quarter inch area without popping a shot at times I see it wants to be at .020 off the lands. I'm pretty sure my barrel will speed up a bit soon and I think I will stick with it for awhile because the bullet has shot consistently @ 2863 - 2869 fps with 32.5 gr. of Varget over a period of several days and temp changes with this being seat depth and bushing size checks. Planning to put the tuner on it next to see if it may have anything left in small groups that it wants to show me.

 

[DeerHunter82]

Thanks, Bill. Good info. I was just playing around with some Ramshot Hunter in my 6XC. Found a decent charge. Will take into account your seating depth results as I am shooting the DTAC.

 

[Bill Norris]

Thanks, Bill. Good info. I was just playing around with some Ramshot Hunter in my 6XC. Found a decent charge. Will take into account your seating depth results as I am shooting the DTAC.

Absolutely welcome Sir. Hope it works well for you.

 

[ShtrRdy]

This screen shot is from the Precision Rifle Blog website

 

[Straightshooter1]

Thought I would pass on a little info I have found with the DTACs. It has been said in various places online that the DTACs wanted to shoot @ .010 - .020 off the lands. When I first started messing around with it in a shooting buddies 6XC I saw that if I got any closer than .007 to the lands it did not want to group. I then tried some loads in my 243AI and again found it wanted to be at .010 or more away from the lands in order to group well. Just recently I started working with it in my new ODCR 6BRX and have again found that it wants to be at .020 off the lands to group well. It will shoot decent closer to the lands but in order to stay down in the quarter inch area without popping a shot at times I see it wants to be at .020 off the lands. I'm pretty sure my barrel will speed up a bit soon and I think I will stick with it for awhile because the bullet has shot consistently @ 2863 - 2869 fps with 32.5 gr. of Varget over a period of several days and temp changes with this being seat depth and bushing size checks. Planning to put the tuner on it next to see if it may have anything left in small groups that it wants to show me.

Hmmm??? Would you say that distance from the lands is more important than seating depth?

I'm asking because they're really not the same thing, as different chambers are different sizes. Like .010 - .020 off your lands could mean when I seat to that off my lands my cartridge could actually be .040 longer in seating depth.

 

[Bill Norris]

Hmmm??? Would you say that distance from the lands is more important than seating depth?

I'm asking because they're really not the same thing, as different chambers are different sizes. Like .010 - .020 off your lands could mean when I seat to that off my lands my cartridge could actually be .040 longer in seating depth.

Yea I get your point and agree. Thats why it is so important to test in each rifle to find that place where the rifle is happy. I was just mentioning my experience simply because I saw it at three different distances from the lands and all were off the lands. Moving closer to the lands increased group size in all three.

 

[Bill Norris]

I guess I should say I did not try seating into the lands from just touch with either rifle so I cant say whether that would increase or decrease group size.