Favorite Bullet Seating Depth tool?

GaryO, this is a good topic and I will follow this thread, although it has been covered before it is worth hashing out again. I have a Sinclair, Stoney Point and other methods of finding the lands. I use the Stoney Point a lot, the argument against the Stoney Point is the unfired case as it relates to head space and this is a good point, but I find it a great tool to get you close and adjust from there.
Dave T
 
I use the Stoney Point/Hornady Lock and Load gages. I added a guide to it to center the gage in the action, which gives me more consistent measurements. Like DaveT said, it is a starting point. I also have a drill and tap so I can make my own cases for calibers that I need. - nhk
 
Yes nhk, we also drill and tap our own cases after being fired a couple times. But please show us a pic of your centering guide.
Dave T
 
Gage guide

The guide is 1.25" long X .375" ID and .695" OD and is held in place where ever you want it by an o-ring slipped on either side of the bushing. I did this before I got my lathe, so I used bronze bushings from Ace Hardware. Now I would make one out of Delrin or aluminum. I slide it to where it is centered in the rear of the action and you can see it holds the case pretty well centered. - nhk
 

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I like the Sinclair tool. It allows me to check a variety of cartridges without needing a seperate tool or adaptor for each one.
 
Explanation please.

TedH said:
I use a dummy round with some lube on the ogive area of the bullet.

Ted
Click to expand...

Ted - Could you explain how you set up and use the dummy round and what you are looking for? Thanks. - nhk
 
I'm firmly with Ted.

I think that adding tools only increases the likelihood of tolerance stack.

I don't use lube like Ted does but other than that....... here's how I've done it. Several options.

Most often I simply deprime a case, run thru the resizer to set the neck tension at about .001-.0015 interference to overcome the ejector plunger spring and have at it. I seat a bullet 'long,' measure, close the bolt and remeasure to see that it moved. The remeasured round is "jamset" by the rifling lands. No tools, it's actually set by the rifle, in the rifle, on one of your own rounds.

Some alternatives;
-remove the ejector if you're REALLY trying to find .000 engagement (I dunno WHY but anyways...)
-color the bullet with a silver sharpie to easily see engagement marks
-slot a neck with a small saw for an adjustable tension round
-simply tap a small ding in a fired neck if in the field

etc etc... all better ways than interjecting an unnecessary tool.

opinionsby


al
 
if one uses thier own fired cases, no need for a centering tool. drill and tap your own case....no issues.
i did make expanders to get close to zero bullet hold, and still straight.
use the same bullet as the bbl wears, so the measurements mean something.
i do not go for jam, but for touch. the same touch a machinist uses when using a mic. touch, not a c clamp.
my issue with those that do jam is that in my opinion it is not precise. how many of you have optical comparitors to measure the lenght and width of the marks ??
and a newly chambered bbl will not have the same "seat" /contact as a worn fired bbl.....so how does the initial measurement relate to later meaurements ?
again just my opinion.
( so yes i use the basic stoney point tools but typically my own cases.)
mike in co
 
bob, that is just one more reason to be able to measure where the lands are not not some amount of jamb based on lenght eguals width, ot twice the width..etc.
mike in co
Bob Kingsbury said:
Contrary to popular opinion, not all barrels shoot at jam
Click to expand...
 
I do it pretty close to the way that Al explains it. However after I seat the bullet in the case, I put a bit of case lube on the bullet so it doesn't get stuck in the lands and pull out.
Then I know where the lands are. I use a fairly long pointy bullet with a 10 GO so there isn't to much of the bullet left in the case next when by the time I give it about .005 jam.
Ted
 
Dummy round

TedH said:
I do it pretty close to the way that Al explains it. However after I seat the bullet in the case, I put a bit of case lube on the bullet so it doesn't get stuck in the lands and pull out.
Then I know where the lands are. I use a fairly long pointy bullet with a 10 GO so there isn't to much of the bullet left in the case next when by the time I give it about .005 jam.
Ted
Click to expand...

I was wondering if you were looking for the jam length or a certain amount of rifling engraving. I've done that (without lube) and stuck a few bullets, or had different lengths due to some of the bullets getting pulled back out slightly on extraction. I prefer to see where they just 'touch' and then adjust from that length, which for me is 0.010-0.015" jump for 'naked' bullets and 0.010-0.020" jam on coated bullets. I always keep in mind I may need to extract a round and a pulled bullet sure can make a mess. Thanks. - nhk
 
Gary O said:
What say you?
Click to expand...

I use the bullet itself in a dummy round looking for either a square mark or a mark twice as long as it is wide, at the ogive, depending on how deep I want to seat it. With my 6PPC I use .003" to .004" neck tension, that N133 seems to like, so I've never had a problem with bullets sticking in the barrel.
 
I've been using the "slotted case" method that alinwa mentioned. I start with a once fired case and dremel three spaced slots in the neck. With the bullet set long I can feel the contact. I do have to be careful and not drag the round on extraction. Has made it easy/quick to change bullets. Regards
 
I tried different tools and finally settled on the Davidson base and nose pieces sold by Sinclair. With these, I can hit my desired OAL spot on. I usually seat about 5 or so thou high, and sit them in a loading block according to their height above my desired OAL. The block identifies each row by .001" increments.

Best way to find where a bullet is just kissing is to mark a cleaning rod at muzzle with bolt in gun, then remove bolt and insert a bare bullet in the chamber. Mark cleaning rod again when it contacts bullet meplat, difference will be OAL for that bullets. But don't stop there. Load a dummy round and after bullet is shined up with 0000 steel wool, try it again until you can just barely see contact with the lands. On factory barrels, this is sometimes difficult.

PS - The Davidson nose pieces can be used to measure bearing length if you buy two nose pieces in that caliber and attach them to your caliper.
 
and just where do you get a precise tool to measure to the "mark" on the cleaning rod ??
you are kidding me right ??
you sort loaded rounds by .001...but use a "mark" on a cleaning rod to find when they just touch ??
....and why are your loaded rounds off from the correct/desired length ??
what ???
mike in co
tenring said:
I tried different tools and finally settled on the Davidson base and nose pieces sold by Sinclair. With these, I can hit my desired OAL spot on. I usually seat about 5 or so thou high, and sit them in a loading block according to their height above my desired OAL. The block identifies each row by .001" increments.

Best way to find where a bullet is just kissing is to mark a cleaning rod at muzzle with bolt in gun, then remove bolt and insert a bare bullet in the chamber. Mark cleaning rod again when it contacts bullet meplat, difference will be OAL for that bullets. But don't stop there. Load a dummy round and after bullet is shined up with 0000 steel wool, try it again until you can just barely see contact with the lands. On factory barrels, this is sometimes difficult.

PS - The Davidson nose pieces can be used to measure bearing length if you buy two nose pieces in that caliber and attach them to your caliper.
Click to expand...
 
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