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I bought some cast bullets online that where .286 in diameter. The problem is that the bullets had to be seated deeply into the case to stay off the lands. Needless to say accuracy wasn't consistant. My groups varied from 2.5 inches to .246. I did some reading when I returned and found that the Lyman reloading manual says to run the bullets through a .277 H & I die so that they can be seated further out.

My question is can I do this to the bullets that I have? Is there somewhere online that I can buy a cast bullet of the configuration that I need to get the accuracy that I'm trying to get? Has anyone else tried shooting cast bullets out of a 7 SAUM and if so what loads did they use.

Any information will be greatly appreciated,

bluecollar
 
Posts: 40 | Registered: 19 December 2002Reply With Quote
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bluecollar,
Sure seems to me that .277 would be much to small to shoot in a 7mm (.284") diameter caliber. I shoot .278" in my 270 Winchester cartridge. The .286" should be right for your 7mm caliber--it's the same diameter that I shoot from a 7-30 Waters. OR, am I reading your post incorrectly? Good-luck...BCB
 
Posts: 212 | Location: WESTERN PENNSYLVANIA | Registered: 11 March 2001Reply With Quote
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Bluecollar,

I too have found this mention on the old Shooters site in relation to the RCBS 145gr bullet being used in a 7BR. It was to 'nose size'a portion of the the nose only to allow the nose to bore-ride. If this is the bullet you have bought, you may find the same bullet made from a different mix will in fact allow normal seating. This was the case with said bullet in my 7BR XP.
 
Posts: 41 | Location: new zealand | Registered: 15 November 2001Reply With Quote
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Sorry for the confusion, the resizing was indeed to be done only on the nose of the bullet. This would allow it to be seated further out of the case and keep the the nose from engaging in the lands of the barrel.

Where I have these bullets seated now puts the base of the bullet about even with the shoulder of the case. They have to be this deep so that I can close the bolt. So it seems if I can just resize the nose of the bullet it would allow me to seat them farther out, which I think was the concept in the article that I read.
 
Posts: 40 | Registered: 19 December 2002Reply With Quote
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Blue Collar. It would help to know what weight bullet you were shooting and what velocity you were trying to achieve?
When you say, "about even with the shoulder of the case" do you mean at the top of the shoulder where the neck ends, or at the bottom of the shoulder where the rest of the case begins? The more info we have, trhe easier it will be to diagnose your problem.
Paul B.
 
Posts: 2814 | Location: Tucson AZ USA | Registered: 11 May 2001Reply With Quote
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I'm shooting Beartooth bullets 140 grain LFNGC at .286". The base of the bullet ends up about even where the cases shoulder begins to neck down making the transition to the neck. Meaning the fat part of the case.

thanks for any input,

bluecollar
 
Posts: 40 | Registered: 19 December 2002Reply With Quote
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OK. If I understand you correctly, the base of the bullet extends into the powder area. Not the best of situations concerning accuracy, and should the gas check fall off, pressure problems could occur. I had this happen one time when shooting 160 gr. cast bullets in a 6.5 mannlicher. The base of the bullet extented into the powder area and the non-crimping old style Lyman gas checks were not the tightest fitting I've ever seen. I had a primer blow with all kinds of gas blowing into my face. The primer pocket looked like you could drive a Mack truck through it. It couldn't have been an overcharge as the load I was using would have overflowed the case had I double charged.
What I think is happening is the heat of the powder igniting is probably melting a bit of the metal on the part protrudinging into the case and slightly altering the bullet making it inconsistant. It becomes a mild balance problem. If you can size the nose down a bit, so that it will enter the throat, that should allow you to properly seat the bullet and accuracy should improve. You might also want to consider a different bullet with a more friendly nose shape.
Paul B.
 
Posts: 2814 | Location: Tucson AZ USA | Registered: 11 May 2001Reply With Quote
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Paul,

I think that you hit the nail on the head. I never considered the gas check coming off but I did have one case that did exhibit high pressure, now I know a possible cause. Now that you understand my problem, would it be possible for me to resize the nose of the bullet like I read about using a .277 sizer? Also, do you have any idea where I could just buy some bullets that would better fit my needs online so that I can give them a try?

Thanks,

bluecollar
 
Posts: 40 | Registered: 19 December 2002Reply With Quote
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I think sizing the nose to .277 is reducing them a bit too much. What you want is a nose that will just slip into the bore mildly snugly, yet not be so tight so as to push the bullet back into the case. You need that nose to be supported by the bore to keep it properly aligned. Normally, I try to find a bullet that will go no deeper into the case than the junction of the neck and the shoulder. If the nose is slightly larger than bore diameter it is lightly engraved by the rifling which is good.
I don't know who makes it on a commercial basis, but in that bullet weight, try the RCBS 7mm-145-SIL. I've just started playing with that one in a 7x57 and first results seem to be promising.
Here's one way to tell if a certain bullet has promise in your gun. Take the bullet in question and try to insert it into the muzzle of the gun. If it's too loose, it will never shoot well. It should be a very snug but easy entering bullet. If it is too big and engraves on the rifling, not all is lost. If the bullet is short enough that the base does not go below the neck/shoulder junction, and is just barely engraved by the rifling when chambered, then it could very well be the best shooter of them all.
Now, if you're going to try and size bullet noses down, I'd suggest maybe .279-.280". The thing is, do you have a luber-sizer tool? Another question is, does someone make a sizing die in one of those sizes? Lyman makwes one in .278" which might work. If it didn't, I have a URL to a fellow that will enlarge it to any size you think you'll need.
BTW, I know you're shoot a 7mm of some kind, but which kind? 7x57? .280 REM.? 7mm-08.? It would help if we knew.
Paul B.
 
Posts: 2814 | Location: Tucson AZ USA | Registered: 11 May 2001Reply With Quote
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Thanks for the input. I don't have a lube/sizing die but have been considering getting one to start casting my own bullets. I did however in the mean time find a company that sells a 150 grain, 7mm silhouette bullets. Judging by the picture they look like they will work for my application but I won't know until they arrive.

I just started trying to shoot cast bullets out of my 7 SAUM and plan on using them in my 7-08 as well. I've shot them in my 375 H&H with great results and found that not only are they inexpensive to practice with, but they can be very accurate as well.

bluecollar
 
Posts: 40 | Registered: 19 December 2002Reply With Quote
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