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Posted: 5/4/2016 12:29:08 PM EDT
[#1]
Quoted:
Using the same FMJ data for coated lead bullets my lead bullets seem to touch the lands.. barley. I always get hesitant to shorten my OAL. My question is, are coated lead rounds acceptable to touch since they form down easier than FMJ? Here are my loads.. 9mm 147gr coated lead with N320 3.0gr @ 1.135 3.2gr @ 1.142 3.5gr @ 1.142 3.8gr @ 1.142 300blk 203gr coated lead @ 1.95 with A1680 10.2 @ 1.95 10.6 @ 1.95 11.0 @ 2.00 Shorten your OAL, touching will cause more increased pressure issues then reducing case capacity. OAL is always bullet and firearm specific, Never manual specific. |
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Posted: 5/6/2016 9:20:43 AM EDT
[#2]
OAL had to go down to 1.075-1.085" to fit the majority of the 147gr Lucky13 bullets, although they did fit, this seems too short for 147gr.
Am I ok with that? Anything to look for? Thanks |
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Posted: 5/6/2016 9:50:55 AM EDT
[#3]
What's your data say?
Lyman 49th shows a lead 147 @ 1.058, but doesn't list that powder. It is a different mold than L13 uses, probably closer than fmj though. Nothing against L13, great guy and perfectly content with most of their bullets, but I had to give up on their 147, the molds drop a pretty wide weight variance and a big size variance as well which combined with the sizing method leads to an inconsistent ogive and necessitated deep seating that was still occasionally jamming the lands hard, only ill effect was during ULSC, the accuracy was acceptable, but never great. |
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Posted: 5/17/2016 8:53:42 AM EDT
[#4]
Quote HistoryQuoted:
What's your data say? Lyman 49th shows a lead 147 @ 1.058, but doesn't list that powder. It is a different mold than L13 uses, probably closer than fmj though. Nothing against L13, great guy and perfectly content with most of their bullets, but I had to give up on their 147, the molds drop a pretty wide weight variance and a big size variance as well which combined with the sizing method leads to an inconsistent ogive and necessitated deep seating that was still occasionally jamming the lands hard, only ill effect was during ULSC, the accuracy was acceptable, but never great. I noticed that as well.. I bought a few companies 124-147gr to test and ill see if any of the others get any better. |
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Posted: 5/17/2016 6:16:06 PM EDT
[#5]
Quote HistoryQuoted: Shorten your OAL, touching will cause more increased pressure issues then reducing case capacity. OAL is always bullet and firearm specific, Never manual specific. There's enough evidence, particularly with straighter-walled cartridges, that this isn't always true. |
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Posted: 5/17/2016 8:08:02 PM EDT
[#6]
Quoted:
Using the same FMJ data for coated lead bullets my lead bullets seem to touch the lands.. barley. I always get hesitant to shorten my OAL. My question is, are coated lead rounds acceptable to touch since they form down easier than FMJ? Here are my loads.. 9mm 147gr coated lead with N320 3.0gr @ 1.135 3.2gr @ 1.142 3.5gr @ 1.142 3.8gr @ 1.142 300blk 203gr coated lead @ 1.95 with A1680 10.2 @ 1.95 10.6 @ 1.95 11.0 @ 2.00 You have two problems going on. 1. lead bullets, being either waxed or PC, will produce higher working pressures than copper jacket bullets when loaded to the same loads. So in regards to the 9mm loads since these are full power loads, work your loads up and watch the primer for signs of over pressure. In the 300blk, these are not full power loads, you should be fine with them. 2. Leave some room for bullet jump to lands!!! This will make sure that the round can load into the chamber/firearm without the rifle jamming on loading. Also, with some loads engaging the rifling on loading (pressure spikes) and some not engaging the rifling (jump to lands), your deviations of speeds are going to be all over the map (less accurate). Simply, with cast lead bullets, make sure that you have at least a .004" jump to lands as your norm. Some may be slightly less ,while some may be slightly more due to the coating, but with all having at least a small jump to lands on ignition, will not run into a feeding problem and will have less deviation of speed spreed through the shot strings. |
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