XTP bullet seating variations - 38 Special - what's normal?

[RealGun]

FWIW; I can't remember when I last measured OAL of any revolver handload (38Sp., 357 Mag, 44 Sp., 44 Mag., 45 Colt). I use 90% cast bullets and seat bullets to the crimp groove. My jacketed handloads the bullet is seated to the cannelure and I don't use smooth sided (plated) bullets in revolvers. I seat to the groove/cannelure and disregard book OAL. I figgered long ago the bullet designers knew where to locate the groove/cannelure and I have rarely found seating to the groove/cannelure rarely matches book OAL. In 40+ years of revolver handloads I have never had a problem from seating as such and assembled many very accurate loads (more accurate than I can shoot!)...

I stopped writing OAL on my ammo boxes, like the label providing a spot was demanding I measure like a good little reloader. How the crimp looks is what I to go on. The exception is 327 Federal Magnum (in a Single Seven), with which 32-20 RNFP lead bullets are sometimes too long in ogive. I have to test whether the gun chambers will accept the cartridges as loaded.

 

[mkl]

Micrometers are generally more accurate than calipers. Ebay frequently offers Starrett for sale at very reasonable prices. In addition to the regular micrometer, I picked up a Starrett blade and a Starrett post micrometer for less than $20.The post is useful for measuring neck wall thickness while the blade will allow measurement in tight spots (extractor groove diameter for example. The blade will also allow exact measurement at any point on the bullet ogive.

 

[JD Fla1]

looks like my caliper was off ! Thanks for that little, but huge TIP !
I bought a new iGaging ABSOLUTE ORIGIN 0-6" which seemed to have great reviews.
the xtp's are now measuring a good .357. Now, my trims in my .556 pile are slightly longer than 1.750, probably not a big deal though for range ammo.
My other caliper did take a fall once, and it hit my foot before the floor, so I didn't think much of it, as it still read O at its closed point after that.

I'm going to echo out - to always have at least 2 measuring devices for each procedure.
I do have 3 other weight scales, and check weights, to check my matchmaster lite scale also, includes a cheapo beam scale by Lee.

I'm back to using the M.A. die for sizing and the Lee flare and fill die, M.A. seating die, and Lee F.C. die. producing a very slightly bulged case at the bottom of where the bullet has seated to.
some of these mixed cases you can see it, other you can't. Nothing is able to be pushed back with some good force against the side of my bench before light crimping.

You guys are great - Thanks -

 

[forrest r]

It's good to keep check gauges around like these for the calipers & micrometers. Some of the gauges I use along with the wrenches for adjusting/re-setting the mics if needed.


Square block gauges are also a good thing to keep around to check calipers after you open them up to 1"/2"/4"/etc.


I have several calipers and mics, 99%+ of my needs are done with 6" calipers and a 1" mic. Those gauges pictured above were bought on e-bay for $15 shipped. Well worth every penny to be able to verify what I'm measuring with is actually correct. Along with having the ability to re-set/calibrate my calipers & mics if need be.

 

[stonebuster]

I'm waiting on a new caliper, got to have something to compare it to I guess. Those .357 bullets measuring at .356 are bugging me.

Out of curiosity, I just measured three at random with my calipers and all three were .357 edit: I'm using the same calipers you bought. I'll have to keep an eye on them or get a micrometer to double check it.

 

[JD Fla1]

my luck the older one I bought a few years ago was out of spec. The new one reads 4 decimal places in bold.
what is abss? is that the same as zeroing ?

so, I thought I was going to load some up today, but - I bought the inline fabrication quick change stand and setup for 2 of my 3 presses, and I ordered the output bin bracket for the auto breechlock pro, and they sent me one for the left side, not the needed right side. - sent them an email 3 days ago, no response yet.
I ended up loading some .556 for the first time on my T7, with Berry's 69g. hpbt -
I want to use the BLP for hand gun and the turret for rifle, love that case feeder on the BLP -