Friday, September 26, 2003

So, now I've got time to discuss recent events.

First, I thought I'd sit down with the 7mm TCU and form some more brass. Let me digress a bit and say that I like to have lots of ammo on hand. I don't know why, but I do. Anyway, I wanted to form some more brass for the 7mm TCU and after I ran the mil surp brass through the sizing die I needed to fireform it. Looking around on the bullet shelf revealed that I had 140 gr. Nosler BTs, 139 gr. Hornady FPs, 120 gr. Hornady VMAX (the replacement for the discontinued SSP) and a cast 140 gr. FPGC from Beartooth Bullets. Due to the shortness of the 7mm TCU neck, I don't think it is suitable for the cast bullet (I don't want the lubed bullet to extend into the body of the case or for the lube grooves to be exposed).

I decided to load up some of the 139 gr. Hornady FPs over 25 gr. of H4895. These bullets were intended and purchased for loading in my 7-30 Waters (also a Contender carbine) but I was not really excited by them in that cartridge and they were going to sit on the shelf if I didn't use them now. I had my Chrony along with me and these clocked an average of about 2000 fps from the 21" 7mm TCU. Now that's not moving very fast but it was accurate, giving 1-1¼ inch groups at 100 yards. Accuracy out to 150 yards was gratifying. So...

I wanted to see if I could speed it up to forecast velocities (the manual showed 2100+ fps in a 14" barrel!), so I loaded it over H335, a slightly slower powder which might do a bit better. Velocities with the H335 did get 2100+ fps but not plus by much! Mine must be a "slow barrel" as it gets only 2400 fps with 29.4 gr. H4895 and 2450 fps with 30.5 gr. H335 under the 120 gr. Hornady OR 130 gr. Sierra SSP bullet. Getting back to this particular load, the H335 charge didn't change accuracy one iota. I think this is a pretty good bullet, but I don't know in what application I'd use it. It gets a full 400 fps less in the TCU than in the Waters cartridge. I don't even know if it matters as I've run out of those bullets, don't plan on buying more and have moved on...

To the .30 Herrett (again). My base, standard, load is the 130 gr. Hornady SSP over 24 gr. of H4227. This exceeds the manual recommendation (but I've seen it elsewhere and in an older manual) so once again I can't accept any responsibility for your use of this data or application of this information. This load gets about 2200 fps from the 14" barrel with the Choate extension (now discontinued). It will give groups of about 1-1.5" at 100 yards. I understand that this bullet has also been discontinued by Hornady. It is hard for me to understand why. Perhaps somebody can explain this decision to me.

I thought that perhaps I might find a "varmint" load which I could substitute for my all purpose load using the SSP bullet when hunting groundhogs and coyotes. To that end I bought some Hornady 110 gr. VMAX. Looking over the various manuals, I came to the conclusion that 23 gr. H110 under this bullet would provide the best ballistic performance. The first test cases I loaded up to this level were primed with the CCI 200 primer.

I must digress again to say that while it is often recommended that one use Magnum primers with the ball powders, I've found that it is not necessary but also not always the best performer. However, the recommendation is not made lightly and it was true in this case!

Velocities ranged from 2490 to 2190 fps and the SD was 121! Clearly unacceptable, I thought to improve things by switching to the CCI 250 (a "magnum" primer) and adjusting my dies to give a stronger or tighter crimp. This did the trick! Not only did the average velocity come up but the SD dropped to the lower double digits. This had to bode well and it did. A 3 shot group at 100 yards (the target fell during the string) was less than 1" and cluster around the "X". I still don't know if Hornady intends for this bullet to replace the SSP, but at least I have a load for it.

I've also been messing about with the Leadheads PN30-149G .310" bullet. Using 5 gr. of Unique gave an average velocity of 892 fps and 12 gr. SR4759 gave 1320 fps. If I remember correctly, that's 245 and 575 fpe respectively. We're talking .32-20 power, suitable for small game and that is my intent. However, it is a bit more bullet weight than necessary so I was going to order a 115 gr. bullet from Beartooth Bullets but the on-line system would not work for me today. Oh well...

I need to get out and chronograph the .38-55 and .41 Remington Magnum loads. I hope to post the results and my comments on Tuesday.

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