Loading question on 170 gr Moly LRN in 38spl

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Wayne K

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Bear Creek was out of 158 LRN so I brought home a couple of boxes of 170 LRN. Heard they were the new rage at ICORE so why not. I need to load up a batch for my wife (Model 627 PC 5") and no time to Chrony for now. Any suggestions? I have BE, Unique, Herco, 231, 2400, PP etc. These are .358 x .750 no rings...smooth. Primers are Federal SP
Thanks!!
 
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No crimp groove? That's a bummer for a revolver bullet.

I would use a slow powder such as HS6, SR4756, or 2400. Lyman #49 lists an HS-6 load as 5.0 to 6.4 grains for their 170 grain SWC, giving 677-856 fps. SR4756 is 4.2 to 5.4, giving 645 to 836 fps.

Surprisingly (to me, anyway) Universal Clays gives the highest velocity. The load for it is 4.0 to 4.5 grains, yielding 799 to 912 fps.

edit: I had to go back and correct a load figure. I'd typed a load for UC that was 1/2 grain over max; good thing I reviewed my post. But that is an example why you should verify any load you get off the internet prior to trying it.
 
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I'd always heard that if you go moly, you can't go back. Once the moly gets in your bore it actually acts like an abrasive on non-moly bullets and may cause a lot of fouling that wouldn't have been there otherwise. I've never verified this so please let me know if you experience it. Thanks.
 
Thanks cp1969. Actually not too worried about lack of grooves. I shoot a LRN with a hollow base (no grooves) and works fine in 1917 & 625 revolvers. The Bear Creek rounds are 12-13 hardness so a medium crimp bites into the lead round quite well. No lube requirements obviously as these come Moly coated.

Jelly bean - not an expert on Moly. According to Brownells, Moly can be stripped with Kroil & J&B bore cleaner. Tried it and seems to work fine. What I did learn by experiance and some old hands at ICORE is that you should not clean the bore in the middle of a match. Brush ONLY. Once you scrub the moly aggressively with patch/Kroil/JB etc, you need to shoot a fair number of rounds to uniformly coat the barrel. Since I shoot only lead in certain revolvers for plinking, range shooting and ICORE, I'm not concerned about commiting to Moly.
 
Wayne, thanks for the information on shooting moly. I've always avoided it based on what I'd posted above, which I read long ago in the Varmint Hunter magazine. Plus the fact that it didn't do any better for me in the .223 I did try it in.
 
I have a friend that shoots a lot of long guns competitively that won't use Moly...say's he has had experiance where "rings" have formeds in the barrel. I only know that a lot of the ICORE shooters really like it, and I have had no issues in S&W revolvers or Kimber autos.
 
I've shot thousands of moly coated bullets over the years with no problem. Biggest improvement is less smoke which helps shooting in the early mornings when the sun is in your eyes.

I'd start with 3 grains of Bullseye. You can go up to 3.2 as a max according to Lyman's reloading manual. If you had a chrono I'd tell you to experiment.

The 170s group very well. You can also use 3 grains of Titegroup. 3.4 is listed as the max and also the most accurate load.

Unique would be 3.7 to 4.2.

All of these will make Minor with space to spare.

Good luck
 
Wayne, or anyone else...
I recall seeing a do it yourself moly coating set-up years ago where you put your plain bullets into a tumbler with some moly powder and some steel balls, then when the tumbler was turned on the balls pounded the powder into the surface of the bullet. Does anyone have any experience with do it yourself moly applicators?
 
I have shot many thousands of the Billy brand Moly bullets in .38 and .45 and I don't use anything else. I have never had any problems and it cuts way down on smoke which is a concern for me when shooting IDPA.
For .38 spl I use 4.3 Grns of W231 806.1 average for 10 shots at 75 degrees.
I also use federal primers and these were fired from a 4" 686, Chrony at 10'.
 
So here is what I came up with so far. Bullets are 170gr Moly from Bear Creek. No rings, completly smooth. All cases are R&P 38sp with Federal 100 primers. All are seated a tad high at OAL 1.533 to more or less equal the seating depth of the 158 gr LRN. Medium crimp (when I pull a bullet out of the case, there is a clear ring around the lead from the crimp). Chrony at 10" no wind and 70 degrees.
Herco 4.0 693
Bullseye 3.0 663
Bullseye 3.2 694
Bullseye 3.4 720
Unique 3.8 669
Unique 4.0 720
Unique 4.2 827
Titegroup 3.0 672
Titegroup 3.2 697
Titegroup 3.4 713
I'm loading up a batch seated deeper to 1.490 (beginning of ogive) which may increase pressure/speed a little. Sure a lot of room in the 38sp cases!
My goal is to find the most accurate load at Power Factor (120) for ICORE.
 
The shorter you make them the less noise you will get but your pressure will go up so watch those primers for pressure signs and watch how the cases extract. If cases become hard to extract you've exceeded the pressure curve.

I shoot them out as far as they will go, 1.55.

You need 706 fps to get a 120 pf. I like shooting for 130 pf so you don't have to worry about the chrono stage when you go out of state. For 130 you need 764 fps.

Let us know what kind of groups you are getting. Two inches at 25 yards is pretty good. The 170s shoot great so you can try for 1 1/2 inch groups but it will take a lot of effort to get there.
 
Loading a little deeper should bring you in line with 120 power factor. You need 720 fps. I'd shoot for 760 and a pf of 130 so you don't have to worry about the chrono stages.

That's a great bullet. A lot of guys have switched to it. Funny how your loads don't make minor, according to Lyman you are at Max on some of your loads. I shoot a little hotter. As long as the cases come out easily I don't worry about pressure, that and looking at the primers.

Once you have the velocity you want play around to get the tightest groups possible. Unique has worked best for me.
 
Thanks for the advice AzShooter, on pressures as well as some extra poop for out-of-state chrony . It appears to me that all load data from cast bullets show higher MV than I get from Moly regardless of which load book. I was told at one point that the Moly allows the bullet to move easier, so pressure doesn't build as high, thus less MV. I have crony'd a bunch of 158g LRN and 45 ACP in 200 LRN (Hollow Bae), 200 LRN flat base and 200g SWC and this seems to be consistant. I know you said you shoot Moly, so you may have noticed this as well. Has anyone else out there experiance this? Just want to make sure I'm not looking at this incorrectly. I'll update as I get more data. I am loading test to 1.490 OAL just to see.
 
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