- June 3, 2018 at 6:48 pm #55559Capt45Participant
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I had one of these until last week, and that’s when Tim re-chambered it to a 7.62 x 39. After getting it set up with a scope I put it on paper and had it sighted in in 3 shots. This is going to be my “go to” setting in the brush gun waiting for a varmint or Deer or whatever cause it’s compact, light and easy to carry. At 6#’s + it beats my RPR 6.5 CM by right at 6#’s. Thanks Tim.
- June 16, 2018 at 7:12 am #68470
Glad you like it Capt45.
That’s a really awesome little gun and I’m sure you’ll never wear it out. Awesome idea.
- June 16, 2018 at 12:27 pm #68471kensParticipant
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I had a mauser bolt gun in 7.62×39. it gave me fits to feed correctly, but, it shot very nice groups with mil surp ammo.
It was a .300×308 bore and 7.62×39 chamber. I was surprised how well the x39 throat shot and held groups.
- June 16, 2018 at 2:31 pm #68474
Kens, contrary to popular opinion based on benchrest shooting which has practically zero application to common shooting scenarios, throat angle has little to do with precision nor does having the bullet exactly touching or .015 off the lands. It simply does not matter. Consistent reloading practices, premium bullets, and correct, full pressure powder charges are far more important.
Every common rifle has a minimum and maximum group size it is capable of shooting with modern bullets of the correct diameter (that’s groove diameter +-.002). This is a set reality that cannot be changed and has to do with the quality of the barrel, and the cartridge being used. Take a common bolt action rifle in say 30-06. You take it out with two factory loads and two hand loads. Shoot ten shot groups. You’ll find that the difference between what the rifle “likes” or “doesnt like” is about 1″ worth of difference. Your best ammo may deliver 1.25 and your worst 2.25. You get the feel for that and record it as fact. Now, go and take the load the rifle “liked” and monkey with the COAL from SAAMI standard to touching the lands. You will probably find that your groups are anywhere from 1.0 MOA to 1.5MOA. .5MOA is about all the difference you’ll have between seating depths.
If you get larger swings than .5 MOA, you’ll also find that even with the best load, there are unexplained fliers in every range session, but (coincidence I’m sure) those unexplained fliers will never boost your groups larger than the worst ammunition produced (2.5MOA in this case).
The point is, regardless of throat configuration or seating depth, a rifle is going to function within it’s limits and there’s almost nothing you can do to reliably change that short of rebarreling.
As throats go, the longer, gentler ones are more forgiving than the short abrupt ones which is why europeans have used them since the dawn of the metallic cartridge era.
- June 16, 2018 at 4:42 pm #68475kensParticipant
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Well, my point was that I read so much talk about how the throat must fit so perfectly & exactly, and this is x39 chamber (loose throat) with a .308 bore (tight bore). I tried cast boolits and it does well, and I hit Larry’s rpm threshold limit, with this little case.
I didnt want to believe the large throat could shoot as good as it did, considering all the talk about throat fitment.
- June 27, 2018 at 11:45 am #68518
Yeah, I hear you loud and clear Ken, but perhaps you won’t be so surprised in the future?
Given the rifle is a set entity, feeding it quality ammunition made with quality components and correct powder charge makes all the difference.
One of the big problems (pun intended) with getting cast to play right in other cartridges is trying to get a cartridge with large case capacity and fast twist to play right with a cast bullet. Using a small case like you are, with a large bullet lets you shoot within the RPMTH of the cartridge and still have a full case of powder.
You get to have your cake and eat it too, just like 30-30, 35Remington, 358 Winchester, and 30BR. There was a reason we REDUCED the case capacity on the 30-06 to create a cartridge (30XCB) that would shoot cast lead FASTER……
Suffice it to say, you’ve got a lot of big stuff going for you with that cartridge, so the minutia of throat depth doesn’t end up being as big of a practical issue as you might think.
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