Using new Starline brass, Remington small pistol primers, 3 grains of IMR Trail Boss, and Magtech 158 grain LRN bullets. The minimum COL (per Lee) is 1.475, however seating the bullet to this length places the only cannelure (lubed) way below the case mouth. IMR suggests a minimum COL of 1.445, so I'm not too concerned about that. I've only crimped the casings just enough to remove the bell. I'll be using a S&W Model 10 for these rounds - in your experience, do you guys think the bullets will manage to walk out enough to impede function of the revolver?
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February 1, 2013, 11:40 AM
Does the bullet have a crimp groove?
That governs OAL in a revolver.
If not, (I just looked on Midway and it does not.) you can taper crimp anywhere in the front band between the lube groove and the shoulder between bearing surface and nose ogive.
Or you could roll crimp over that shoulder.
3 gr of Trail Boss is not a lot and OAL is not critical like it is with a maximum load in .40.
February 1, 2013, 11:42 AM
Your cast revolver bullets undoubtedly have a crimp groove molded into them.
Seat & crimp to that and they will be the proper length.
(Oh! according to what Jim Watson posted, I guess not.
Do what he said.)
You can't use "book OAL" because there is no chance the book data used the same brand of bullets you are using.
I don't even bother to measure revolver loads.
The bullet cannulure or crimp groove automatically gives you the correct OAL.
BTW: You might as well bump up the Trailboss charge to 3.5 - 4.0.
3.0 isn't enough.
February 1, 2013, 12:47 PM
Ah, good to know. Thanks!
February 1, 2013, 01:26 PM
I measure the OAL of revolver loads with cannelured bullets after the fact just to fill a field in my logbook.
February 1, 2013, 02:05 PM
Looking at Magtechs loaded ammunition using the 158 LRN bullets, it appears that they roll crimp just at the top edge of the slight shoulder.
February 1, 2013, 06:10 PM
Added a couple of pictures from one of the rounds, to show where the bullets are seated in relation to the case on each round.
March 16, 2013, 12:35 AM
Similar concern, so is nothing to worry about if its not 1.475 (say 1.460ish) I was worried since Lee listed 1.475 as the minimum OAL for trail boss.
March 16, 2013, 03:28 AM
It would help if you provide enough information for people to know what you're looking for. I felt like Sherlock Holmes trying to find what bullet you were loading for.
Trailboss should have the bullet not compressing the powder. That is the minimum OAL. Reading their reduction information for rifle is enlightening for loading anything with this powder. Lee reprints mfg. data. The COL for a 158 gr LSWC loading with trail boss in MR #2 is a typo. It should read 1.455 per IMR.