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Post by edge on Feb 14, 2008 9:10:59 GMT -5
Many folks have bullet/sabot combos that are too loose. Some try knurling with various degrees of success. In the past I have used a paper patch. The biggest question is what thickness paper to use. If you have calipers or a micrometer then your job is easy. Measure a combo that fits the way you like it, then measure the combo that is loose. Divide the difference by two and that is the thickness of paper that you need. For example: You want to switch from a 0.458 hunting bullet to a 0.452 bullet for practice but want to use the same sabot for consistency. .458-.452= .006 divided by 2 = 0.003 Find some paper that measures 0.003 and cut a strip about the width of the bullets bearing dimension. You can either cut the length a little less than pi x the diameter ( 0.452 x 3.14 = 1.419 ) I would use 1 3/8 to be safe. Wrap the paper and insert it into the sabot and it should load the same as a 0.458 bullet. If you have paper that is 0.0015 thick then you need 2 wraps around. Aluminum foil is about 0.0008 thick. An alternative is to cut the length long and make a loop around the bullet, inserting the paper between the petal slits and trimming flush with the sabot like this: edge.
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Post by encoreguy on Feb 14, 2008 9:22:05 GMT -5
Many folks have bullet/sabot combos that are too loose. Some try knurling with various degrees of success. In the past I have used a paper patch. The biggest question is what thickness paper to use. If you have calipers or a micrometer then your job is easy. Measure a combo that fits the way you like it, then measure the combo that is loose. Divide the difference by two and that is the thickness of paper that you need. For example: You want to switch from a 0.458 hunting bullet to a 0.452 bullet for practice but want to use the same sabot for consistency. .458-.452= .006 divided by 2 = 0.003 Find some paper that measures 0.003 and cut a strip about the width of the bullets bearing dimension. You can either cut the length a little less than pi x the diameter ( 0.452 x 3.14 = 1.419 ) I would use 1 3/8 to be safe. Wrap the paper and insert it into the sabot and it should load the same as a 0.458 bullet. If you have paper that is 0.0015 thick then you need 2 wraps around. Aluminum foil is about 0.0008 thick. An alternative is to cut the length long and make a loop around the bullet, inserting the paper between the petal slits and trimming flush with the sabot like this: edge. Edge, didn't the paper patched bullets used in cartridge rifles treat the paper to help it stick to the bullet a little? I have some articles on this subject that I will have to look up.
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Post by edge on Feb 14, 2008 9:59:40 GMT -5
I think that a regular paper patched bullet that is not shot in a sabot has the patch cut to a special shape and wrapped twice around the bullet. The paper is damp and shrinks slightly when it dries.
edge.
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Post by Kevin B. on Feb 14, 2008 11:18:04 GMT -5
Thanks for the good info Edge, this reopens my interest in lighter bullets at moderate speed.
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Post by arrestman on Feb 14, 2008 12:35:06 GMT -5
I've done this and it works!
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Post by Kevin B. on Feb 14, 2008 13:05:46 GMT -5
I've done this and it works! Did the lights just flicker at y'all's house??!!?? That was me having a brainstorm!!! I just tried the paper patching technique with the 195 barnes and blue sabot. Loose sabot issue solved! When I get my new bag of blues from Del's Sabot Emporium, I will group several 195's and several 200 xtp's. But on the brainstorm: I love the Harvester short black sabot but when coupled with a 250 sst, it's way too loose. The sst 250 is .452 give or take. The copy paper (20#) that I have is .0038 inches think. Double this and it's under .008. A bit much. I need .003 inch paper. (16#) Oh the doors of opportunity have opened wide! May I not stumble over the threshold.
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Post by Kevin B. on Feb 14, 2008 14:21:47 GMT -5
Hey guys, take a wild guess at what kind of paper is exactly the right thickness to make 250 SST's work with harvester short blacks!! The monthly flyer from Midway Shooting Supplies paper is going to be what I use this afternoon. It makes the Harvester short black load a bit tighter than the short black mmp w/ the 250 sst. Going to weigh up some powder and go try it.
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Post by Kevin B. on Feb 14, 2008 17:04:28 GMT -5
Just got back from the hayfield. Target set at 100 yards. I was going to group with three different loads. The bullet/sabot is the 250 grain SST with harvester short black with paper patch. My first attempt on a clean barrel was with a 20/50 duplex. First shot on clean barrel, 4 inches high of poa. Second shot...blew sabot. I didn't bother with anymore of that load. I don't know what I was thinking trying a new duplex with a new bullet set up. Oh well... Cleaned barrel with alcohol patch..dry patch. Load up 43 grain 110 with bullet. Blow a sabot..first shot. ( Okay, this bullet/sabot with paper patch is on the verge of being too tight! I mean, it is tight!! I kind of figured with a fast powder like N110 and such a tight combo, there might be problems.....BUT... After a mild barrel cleaning with alcohol patch and dry patch.. I load up 67 grains of N120 and same tight fitting bullet combo. Bang! 4 inches high of bull. Next two shots on a fouled barrel form an inch and a half group. Each bullet loaded consistently: tight! But the sabot held up very well to the 120! A short starter is required to get the bullet sabot combo started...it's that tight. But with N120, there is hope for a long range 250 grain bullets of the .451 and .452 class. I must say, the paper patching technique has opened up some grand opportunity for load development with Harvesters short black sabot.
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Post by ozark on Feb 14, 2008 17:57:38 GMT -5
Looks like the paper insert will help those with loose bores. It also sounds like you are having fun seeking a better method. I think maybe loads are barrel specific and that what loads tight in one barrel would need the paper insert removed to get it down another tighter bore. It is good that we have so many trails leading to destination accuracy.
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Post by edge on Aug 25, 2008 13:48:19 GMT -5
Thanks to Kevin B. we now have step by step pictures
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Post by DannoBoone on Aug 25, 2008 20:41:29 GMT -5
Good knife, Buckooo! ;D ;D
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Post by edge on Aug 25, 2008 20:48:16 GMT -5
Good knife, Buckooo! ;D ;D Extra credit for matching socks too ;D edge.
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