bolt lift

[Link]

6BR 1-8 T custom barrel. Ok trying to find touch. The bolt drops easy but it has a click on the top stroke, the bullet doesn't show rifling marks, but it does show a slight ring as if it's touching the lead [term?] It does this with 3 different 105 class bullets. Do I just start at this depth and increase my B-O by .003 at a time trying to find the right amount of touch or - jam - [jam is a dirty world] lol. I have the guts out of the bolt and the bolt falls easy on a empty case, so I don't believe it's the case. The neck clearance is .003.
Idea start at jam and go in .003 at a time?
ty Don

 

[bugman]

Before you just start winging it, spend some time discovering the cause of this. Assuming it is a quality receiver manufacturer, and the chamber freebore is wide enough for those bullets, that click is probably the primary cam extracting the 200 line of the bullet, before the ejection phase.
I would measure the OD of these bullets, the OD of your turned and loaded neck, the length of that sized brass......and compare all that to the reamer specs.
You are not reaching the lands.

 

[DaveTooley]

Is this is a new barrel? It sounds like a burr is rolled up where the freebore transitions to the leade angle. It happens sometimes. It should go away after getting a few rounds on the barrel. I'd start there and run the powder up to see where the top end is and then checking seating depth again.

 

[fisherman987]

That slight click is due to the bullet being just into the lands. Seat the bullet .001 more at a time and recheck while maintaining slight pulling pressure on the bolt handle until there is no sign of a faint click, that will be your touch point. You can do the same thing with no case in the chamber to establish what the baseline feel is and then match that feel with your case and bullet to find touch. When you start out, the bolt won't even drop due to the pronounced jam into the lands. As you go deeper into the case with your bullet, eventually the bolt will drop, but them you'll notice a click at the top as you open it. Slow down at that point and seat in small increments until the click "just" disappears.

 

[Owens85]

First thing is to make sure the bolt drops freely on the case your using . The slight click at the top is from the bullet still in the lands just a touch . Do as fisherman987 suggest that will get you there.

 

[fisherman987]

Owens85 is right, you need to make sure you start with the case you intend to seat a bullet in and make sure the bolt drops with absolutely no drag. If you don't check that first, the case itself may cause you to get a false feel. If for some reason, you keep seating the bullet deeper and deeper and it still has a drag on the bolt you should retest with a different case. If your cases have sufficient clearance (including at the 200 line), you should be able to get the same result on two cases in a row.

 

[ELR LVR]

To find exact touch point:
Insert cleaning rod and touch the face of the bolt head
Mark your cleaning rod at the end of the barrel (I use tape)
Insert bare bullet into chamber and lightly tap against the base to seat it into the lands
(Lightly)
Insert cleaning rod to touch meplat of the bullet
Mark the cleaning rod at the end of the muzzle again
----------------------------------------------------------------
Measure between these two marked points on your cleaning rod
This will be your over all length with THAT ONE BULLET
Now tap out the bullet and seat it into a case at this new found OAL
This will be your gauge for all other Seating depth measurements of touching at the ogive.
-----------------------------------------------------------------
If something else is going on such as a burr etc this may help you discover it.
If you want to double heck this measurent you just found
Maybe seat a bullet +.030 out and check land marks on the bullet.
If no Land Marks are measured at about .030" in length inscribed on the bullet
, then there is something else interfering.