Thursday, June 15, 2006

Range test

Cast-bullet loads for K31, and a scope mount for the Savage

Having spent the other day being a good boy and taking care of a bunch of stuff in the house and yard, today I said hell with it("I'll finish this stuff after. REALLY I will") and went to the range. Was planning to go Sunday with a friend if he's able to break loose, but between time and weather don't know if he will. So I figured I'd do the load testing & such today, that way if the Sunday trip happens I can concentrate on just fun shooting. Windy as hell today and gusting, but I went anyway.

Ok, I had formed the .284 Winchester brass for the 7.5 Swiss. I figured I'd take care of two things at once by testing some light cast-bullet loads and using those to fire-form the brass to the cases.('fire-forming' being the use of a light load to use the pressure of the shot to form the cases to the rifle chamber). The cases chambered with no problem, but I still liked the idea of making sure of the fit before using them for full-power loads. Some searching came up with the information that the load I've been using for 8mm Mauser should work nicely with the K31 also.

DISCLAIMER: this is the information I found and worked with; doesn't guarantee it'll work with
your firearms, so if you use this info to work up loads start a bit light and work up.

The range I came up with for 2400 powder was 14-16 grains, so I loaded ten with 14, ten with 15 and ten with 16, figuring to try all at 50 yards with five, then the other five at 100 yards. All used the 150grain gas-checked cast bullet mentioned before.

Here's the first five, 14 grains at 50 yards:














15 grains:














and 16 grains:














all fired with the rear sight at the 100 meter setting.

On to 100 yards. I knew these would be low, so I raised the sight to 200 meters. The 14 and 15 grain loads were spread out a fair bit, and down at the bottom of the target, so they're not illustrated here. The 16 grain load, however,














That's right at 2". For a first trial with this bullet and load, not bad. With the sight at 200, POI is dead-on for elevation; the windage I've seen in other firearms with cast bullets: the point of impact is to the right, whereas the POI with full-power loads is dead center. Not all rifles do it, and I'm not sure why it happens. If I were going to use the cast for matches or hunting, I'd definately adjust the windage for them(be nice to find one of the tools the Swiss used for that),
but since this is a practice load I'm not going to move the sights off their current adjustment.

So I can use this same bullet and powder in .30-30, 7.5x55, 8x57 and .308 for practice loads. Excellent.
(correction: I can use the same powder in 8mm, but NOT the same bullet)

Scope Mount

A while back I wrote about a Savage Model 340, a bolt-action rifle chambered in .30-30, and mentioned I'd like to try it with a scope if I could find a good mount. A good receiver sight would be nice, but with the split bridge on this rifle hard to find one that'll work. Checking around I found several mounts. One mounts the scope offset to the left(don't like), one I've read reports doesn't line up with with the bore, and B-Square makes one I read good things about. On a rifle like this one with the four holes drilled & tapped on the left sidewall it just screws on, and it centers the scope over the bore. Midway had one, so I dug up some money and got it. It's aluminum, very light, and comes with rings, screws and a hex wrench. Installing the mount took just a few minutes, and I stuck a Tasco Pronghorn scope on it. It's a decent-quality 4x scope I had available. Here it is from the right side














and the left














With this scope it puts it a touch further forward than I like, and there's just enough room between the bolt knob and the scope bell for a skinny thumb; I had to slide my thumb back to clear. A compact scope, or red-dot sight, would probably clear very well and take care of the forward-position problem. That could just be me, might well make anyone else happy
as is. It's a very solid unit, well made.

Range testing went the way it should: it worked as designed, with no surprises or problems. Definately better than the factory sights to my eyes, and I would recommend it for this rifle.

Remember what I said about cast loads hitting to the right sometimes? I zeroed with the same load I use in my Model 94, set to hit about an inch above POI at 100. So I tried some of the cast loads I use in .30-30. On both these targets, the aiming point is the square, the circled three are the shots fired:





























I like the fact that the practice loads are giving about 1.25-1.5" groups. And that's just a touch larger than what I got with the jacketed loads. Which is beside the point in a scope mount review, but I love it when a plan comes together.

Just for fun, I also took the Finn M39 and put some of the Czech silvertip ball through it. Just resting my hand on the bench for a rest It gave me this at 100:














With the way the wind was gusting, actually shifting me at times, this is a group I can live with.

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