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Post by Dave W on Apr 15, 2016 23:55:18 GMT -5
Back at it after a die adjustment, didn't really solve anything, unless somebody can unscramble this puzzle. Cleaned the barrel after getting a bullet stuck last time out and having to dump the charge through the breech, always a fun thing. Straight charges of H322 as the propellant with the 200 SST full formed and no wads. Started out with 3 foulers @ 60gr H322 and then proceeded to go from 60-68gr in one grain increments. My uneducated guess is somewhere between 61-66gr for the sweet spot, no clue really. No idea why 63gr jumped left. 67gr being to the right was possibly from the lighting. I have two orange dots up high on the backer so I can get multiple groups on the target if a load is hitting low. Thought I was on the dot I was using as a POA but the orange was washing out in low light. Closed my eyes to relieve eye strain and when I opened them again I was centered between the dots. Only speeds I recorded was the 3 foulers, 2679-2716-2733fps. 60 & 61gr in the group timed 2765 & 2770fps. After that the chrony just wouldn't pick up any readings due to the lighting. All 9 shots measured 2.33 CTC, little over MOA if my math is right. Only had the silver sharpie at the range so I went back over them at home to try and have the shot sequence show up a bit better since the silver is a little tough to read. Maybe the more experienced shooters can enlighten me on how to narrow this down some for the sweet spot?
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Post by rob67 on Apr 16, 2016 6:21:01 GMT -5
Not more experienced, but here's my take on this. Since 64,65,and 66 are the only three consecutive charges to group together I would start with 65gr. Providing that 63 and 67 where not flukes. Good shooting and nice report.
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Post by rob67 on Apr 16, 2016 6:31:45 GMT -5
FWIW. The two .392/.400 I have shot using that bullet really like 2800 fps and 3000 fps if that helps any.
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Post by rambler on Apr 16, 2016 8:10:45 GMT -5
Dave, that's still some fine shooting.
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Post by Deleted on Apr 16, 2016 8:41:58 GMT -5
Good shooting Dave, I did allot of research on ladder test, maybe it's something I need to look back into. I've seen write up where they did three shot groups instead of one shot which seem to show your results better. Looking at what you have I think a three shot group would be hard to see any thing more than what you see. The only thing I'd look into is your chrono readings with out those it could show a different story maybe not but speed readings help see things your not seeing on paper. (Never done a full blown ladder test, I'm just guessing.) Wish Nebraska would allow 40 Cal for muzzleloader I'd get one in a heart beat!
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Post by subcalshooter on Apr 16, 2016 8:43:13 GMT -5
Nice test Dave. Time to load up 3 or 5 of each and see what happens, kinda hard to tell what it's like the best out of that since they are all pretty close, minus the two. I'm with Rob, crank it up a bit and it may get even better.
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Post by rossman40 on Apr 16, 2016 13:48:26 GMT -5
With a ladder test you do not look at the horizontal dispersion, the vertical is what counts. Your looking for a charge range that has little change in the vertical. You can look at chrono readings, if you chart out velocity X charge weight you may find a flat spot that will tell you the sweet spot for "the burn". During a POI test it warns you if something went out of spec with internal ballistics. With a POI ladder test it isn't just the sweet spot for the burn but also barrel harmonics. The trick some of the benchrest guys use now is to find the sweet spot for the burn and then use a barrel "tuner" to handle the harmonics.
Kinda tough going off 1 round, then really tough when the difference is within a group size. But if I had to go off that target, I would follow up with 3 shot groups in the 62,63, and 64gr loads. I would call the 63gr shot more of a pull to the left but if you had a probable error in the horizontal of a even a .25 moa it would still be in parameters
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Post by Dave W on Apr 16, 2016 18:46:52 GMT -5
Thanks guys. 62 or 63gr should be in the ballpark of 2800fps. Probably start at 62 through 66gr of several charges and see if it likes anything.
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Post by mcgowen45 on Apr 16, 2016 21:20:12 GMT -5
Not more experienced, but here's my take on this. Since 64,65,and 66 are the only three consecutive charges to group together I would start with 65gr. Providing that 63 and 67 where not flukes. Good shooting and nice report. Dave great shooting, and I will agree with Rob in saying that somewhere around 65gr. will be a good place to start, and go from there, from the shooting you did I will say that you are real close to that sweet spot.
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Post by Deleted on Apr 16, 2016 22:59:06 GMT -5
5 shots have to be around an inch. Nice test and at 200yds to boot.
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Post by Dave W on Apr 17, 2016 9:04:20 GMT -5
5 shots have to be around an inch. Nice test and at 200yds to boot. Yeah, those 5 in the center were just over an inch.
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Post by schunter on Apr 18, 2016 10:57:35 GMT -5
Nice shooting!
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Post by Deleted on Apr 20, 2016 16:08:36 GMT -5
Any update on the preferred charge?
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Post by Dave W on Apr 20, 2016 17:37:39 GMT -5
Any update on the preferred charge? Solid but nothing spectacular, was debating whether to post results or not. Since you asked. 200 SST .037 bushing No Wads 72* Top group was 65gr H322. Timed-2962-2937-2951 for an average of 2950fps, with an ES of 25fps. Bottom group was 64gr H322, only read the 1st shot which was 2929fps due to fading light. Still not happy with the die setting, takes two firm hands to seat the bullet, will adjust and repeat the loads. On a side note, H322 will seep through the bushing. On one occasion I couldn't get the primer to go into the plug, tilted the muzzle down and went right in. Must have been a grain of powder lodged between the primer and the seat in the plug primer pocket.
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Post by rambler on Apr 20, 2016 17:54:28 GMT -5
You are really dialing that bad boy in Dave!!
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Post by Dave W on Apr 20, 2016 17:56:09 GMT -5
You are really dialing that bad boy in Dave!! Thanks, trying to.
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Post by jims on Apr 21, 2016 11:48:53 GMT -5
That looks pretty solid to me for 200 yards.
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