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Post by Lee Martin on Sept 3, 2015 22:33:51 GMT -5
This is David Bradshaw’s doing but it reconnects me with a project of ours from 1993. Here’s the backstory. A forum member, who asked to remain anonymous, sent David some 300 gr WFNs from an LBT mold. I believe he tried them in an FA 83 or perhaps his Ruger ’03 (keep me honest here David). Both are accurate guns and you can’t do better than the guy pulling the trigger. Sadly the bullets flew like bricks at various distances and speeds. Bradshaw decided to perform surgery. We spoke and he asked if I could hollow-point them, thus altering the COF / COG relationship. The step also minimized concentricity issues on the meplat and nose. Here’s a drawing of what he had in mind: I ran 100 for him last fall and they showed promise. But neither of us are willing to draw conclusions from such a small sample. We needed to shoot more of them to be certain. So the unnamed forum member shipped me another 300 to volcano. That was in March and I’ve been derelict in their processing. This past week I finally chucked them in a lathe and am almost done. One batch goes to the caster, one batch to David, and I’ll try the rest: David and I will try these at 100 yards and I’m sure he’ll use his ’03 Ruger or FA. Mine will be fired from the 5-shot .45 Colt at the top of this page; a gun that has returned 3 – 4” at 100 yards with 335 WLNs, 350 LCMNs, 360 WFNs, and 405 WFNs. Basically it shoots and is pretty load agnostic. Reconnection to 1993 - when dad and I started building .30 Streakers we lathe hollowed the tips of 110 gr Speers. This step was necessary to clear the cylinder face. We never went beyond 50 yards on paper but they grouped tight. Our only 100 yard shooting was at a 10” round rock. Amazingly these bastard bullets hit all day long. They proved flat, flew straight, and most importantly they tracked. We’re hoping the 278 grain Volcano will do the same. More to come. -Lee www.singleactions.com"Chasing perfection five shots at a time"
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Post by Markbo on Sept 4, 2015 19:03:36 GMT -5
Would it nit be easier, cheaper, faster and just have a custom mold or 2 made???
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dmize
.401 Bobcat
Posts: 2,825
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Post by dmize on Sept 4, 2015 20:53:29 GMT -5
.......Bradshaws' drawn bullets look better than my cast ones...............
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Post by bradshaw on Sept 4, 2015 22:06:13 GMT -5
Lee lathe contribution to the Volcano tracks better than my drawing. The evidence is in, Make or break proof to follow. The Ruger 03 (pictured on the hood of the Rugermobile) is a shooter. David Bradshaw
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Post by Lee Martin on Sept 8, 2015 19:09:38 GMT -5
Would it nit be easier, cheaper, faster and just have a custom mold or 2 made??? Lathe hollow-pointing allowed us to try different shapes and depths. If the 277 gr Volcano shoots I may cut a mold. If it doesn’t I'm not out time and material:. 277 gr Volcano left, 300 gr LBT WFN right: -Lee www.singleactions.com"Chasing perfection five shots at a time"
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Post by bradshaw on Sept 8, 2015 23:35:59 GMT -5
Lee upon receipt of these .452 300 grain WFN GC detected an asymetric convexity to the "flat point", i.e., meplat. On the lathe Lee restored weight concentricity, which restores static balance. Dynamic balance requires much more, specifically to include pushing longitudinal Center of Gravity rearward to separate it from longitudinal Center of Form. Whether the Volcano chucks the bullet on air as it flies I cannot say, but the theory has intrigued me for decades, and rifleman Martin Hull of Sierra Bullets shared the theory. Limited exposure of the 276-277 grain Volcano has been through the Ruger 03. Pristine. David Bradshaw
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Post by lscg on Sept 9, 2015 0:10:28 GMT -5
very interesting.
would it be possible to do the same thing with a drill press and vise? or would the precision of the lathe be a must?
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petep
.30 Stingray
Central Alabama
Posts: 453
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Post by petep on Sept 9, 2015 4:10:45 GMT -5
I think the Brit's tried this to stabilize 174 grain .303 bullets by using an aluminum "nose" beneath the jacket in order to move the longitudinal center of gravity to the bullet's rear.
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mtngun
.240 Incinerator
Posts: 12
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Post by mtngun on Jan 25, 2018 15:30:04 GMT -5
If Lee doesn't mind I'm going to revive this old thread because I'm extremely interested in the subject. FYI Part II of this topic continues in a separate thread: singleactions.proboards.com/thread/13937/david-bradshaw-photos-vol-xlviiPart III in yet another thread: singleactions.proboards.com/thread/14101/david-bradshaw-photos-volI started my own "Volcano" experiment. My 357 mag control bullet, a 180 gr. bevel base, is not as blunt as David's 300 gr. WFN's, and was not having the WFN's accuracy problems, but nonetheless it's still a blunt bullet and I wondered if accuracy might benefit from a shallow HP? My control bullet on the right. Lathe cutting a shallow hollow point. The tool is a broken center drill that was reground to a sharp point. The resulting hollow point reduced the weight 6 grains, from 183 grains down to 177. The solid nose control load at 100 yards, fired from a scoped 8 3/8" M29-357 (a M29 that has been converted to 357) from the bench. The same load except with the shallow hollow point. Four groups is not enough to "prove" a significant difference, but this was encouraging. In fact it's the best average this gun has turned in to date with any load. I think I'll retest the hollow point in a coated version, since the coated bullets seem to have a slight advantage.
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Post by Lee Martin on Jan 25, 2018 19:58:56 GMT -5
I'm glad you resurrected this Dan. Your tests are a welcome extension to what David and I started a few years back. Our 300 gr LBT couldn't be saved, as proven by Mr. Bradshaw. But that may be inherent to the bullet, not the volcano HP. I'm eager to see how this plays out for you. Please keep us posted. -Lee www.singleactions.com"Chasing perfection five shots at a time'
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Post by bradshaw on Jan 25, 2018 21:22:20 GMT -5
mtngun.... excellent start. While it is premature to draw conclusion, observation applies.
Top four .357 targets----cast 180 Flat Point 6x6 average=4.3” @ 100 yards. Spread between largest and smallest group=2.5-inches.
Bottom four .357 targets----same bullet hollow-pointed, cast 177 HP 6x6 average=3.2” @ 100 yards. Spread between largest and smallest group=0.8-inch.
Not only do your hollow-pointed bullets average 1-inch tighter @ 100 yards, the spread between tightest and loosest group is only 1/3 the spread of the flat point. Even for this sample of targets, the apparent consistency of the 177 HP is significant and I believe it will repeat. I also believe variation in group size with the parent 180 FP will repeat.
Your process is sound. You have made work for yourself, and progress as well. It would be good to see what happens with powder coat with same powder/charge, also @ 100 yards. I suspect the hollow -pointed bullet will hold up better @ 150 yards. The hollow-pointed 177 may hold group @ 200 yards, while the 200 flat point has trouble hanging on. The target will tell. Good show, David Bradshaw
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Post by bradshaw on Jan 29, 2018 9:10:36 GMT -5
Recommend all who pursue accuracy with a sixgun read closely targets posted by mtngun. Testing at distance----reveals information on load stability unavailable at 25 and 50 yards. 100 yards begins to prove a bullet. Since wadcutters are specialized for bullseye, played @ 50 feet, 25 and 50 yards, to target them @ the distance of a football field is useful but not critical.
mtngun.... would appreciate a few notes on the M-29 you rebarreled & recylindered to .357 Mag. How did you time the barrel? Would you venture position of barrel, hand tightened to frame?
On one of our trips to Smith & Wesson in the mid-70’s to have some revolvers worked on, Ed Verge brought his 8-3/8” M-57, to be fitted with 6-1/2” M-29 barrel and cylinder. Ed Verge later installed his .41 barrel and cylinder on a Model 28 Highway Patrolman. At that time, I had never heard of Ruger or Smith & Wesson over-tightening a barrel. THREAD TIMING was part of normal manufacturing and assembly. (Analogous, in mythology. to the 11-degree forcing cone, which some folk persist in believing is a brilliant modern idea concocted by a gunsmith, or writer.)
It would be useful to see 100 yard targets from all four of your 180 .357 bullets----1) grooved & lubed, 2) grooved & powder coated, 3) grooved, powder coated & lubed, and 4) powder coated SMOOTHIE. Jeff “Tank” Hoover might scream, “Redundant! Extra work!” at the lubed PC, yet I am curious how it affects velocity and ES as well as accuracy. Likewise the smoothie. David Bradshaw
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diddle
.30 Stingray
Posts: 469
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Post by diddle on Jan 29, 2018 10:41:29 GMT -5
I always enjoy these threads and, as usual, find this one exceptionally informative. I am especially intrigued by Mtngun’s bullet alloy information. In my experience, it is unusual to see a revolver shooter espousing the use of bullets at 38 BHN. As I reflected on this, the use of reclaimed shot obviously plays a role. Many casters discount the use of reclaimed shot as inferior bullet material because it is notoriously short on tin and low in antimony as only the best shotgun shot contains up to 6 percent antimony and a trace of tin. Shot manufacturers also include a small amount of arsenic in their alloys. It’s this arsenic that will allow the bullet to be heat treated to such high levels of hardness. Have I mis-read something? Am I all wet?
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mtngun
.240 Incinerator
Posts: 12
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Post by mtngun on Feb 10, 2018 13:38:24 GMT -5
I always enjoy these threads and, as usual, find this one exceptionally informative. I am especially intrigued by Mtngun’s bullet alloy information. In my experience, it is unusual to see a revolver shooter espousing the use of bullets at 38 BHN. As I reflected on this, the use of reclaimed shot obviously plays a role. Many casters discount the use of reclaimed shot as inferior bullet material because it is notoriously short on tin and low in antimony as only the best shotgun shot contains up to 6 percent antimony and a trace of tin. Shot manufacturers also include a small amount of arsenic in their alloys. It’s this arsenic that will allow the bullet to be heat treated to such high levels of hardness. Have I mis-read something? Am I all wet? Sorry for the slow response, diddle. This forum does not seem to offer email notifications of new posts so I don't see your post unless I happen to revisit the thread. Anyway, reclaimed shot seems to run about 5% antimony, judging by the density and hardness. It casts well enough to suit me though not everyone may agree, depending on your mold and your casting style. The arsenic increases surface tension and makes it prone to form small bubbles but other than that no major casting issues. I believe both the extra arsenic and the 5% antimony combine to make a nearly optimal alloy for heat treating. Reclaimed shot is also relatively affordable, available for as low as $1 per pound if you are willing to buy in bulk. It's becoming my favorite alloy now that clip-on wheelweight is difficult to find in my neck of the woods. That said, I've since switched to air-cooled reclaimed shot for my 357 revolver experiments because its 11.4-ish BHN seems to give slightly better accuracy, especially in PC coated versions.
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mtngun
.240 Incinerator
Posts: 12
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Post by mtngun on Feb 10, 2018 14:00:10 GMT -5
Some updates on my HP adventures: I did try a coated, HP version of my 357 control load. The HP's groups did not average as well as its solid nose brother, but only because of a single flier. If you disregard that flier then accuracy was no better or worse than the solid nose. I don't know what caused that flier -- the shot felt good -- but velocity had crept up to 1408 fps. Past experience tells me that this load shoots better at 1370 and starts throwing fliers if you push it over 1400 fps, so that may have had something to do with it. Since then I have made some tweaks to my control load to bring the velocity down and improve accuracy and I may retest the HP with the revised load. Getting back to the subject of using a hollow point to improve stability .... I've been doing some meplat experiments, and the 85% meplat bullet seemed like a good candidate for hollow pointing. A very shallow HP similar to Lee's "volcano." Top of the target is the solid nose 85% meplat at 100 yards, bottom of the target is the hollow point 85% meplat. The HP version grouped slightly better but it would take more than 4 groups to "prove" a statistical significance. Meplat results to date, with the revised load: 50% meplat -- 6.38" average at 100 yards 62% meplat -- 4.48" average 75% meplat -- 2.76" average 85% meplat -- 3.92" average 85% with HP -- 3.43" average The bullets used in my meplat experiments are identical other than their meplat, so I figure the differences in accuracy have got to be due to their aerodynamics. Transonic aerodynamics are tough to predict.
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