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Post by rangeball on Apr 26, 2011 9:22:15 GMT -5
Thanks Just heard back from Barnes. I had emailed them asking them to consider making such a bullet, they responded it would be a custom job, minimum order of 50,000 at $.75 per. So if we can get 500 guys that each want 100...
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Post by rangeball on Apr 26, 2011 9:45:19 GMT -5
I was thinking about veral's email over the weekend. I realized I was thinking copper length, and a lead bullet could be shorter which would get he weight down. An all lead bullet poured like he mentioned with a soft nose and the rest hard would could do this-
Ogive.... T5 OAL....... 1.1" BS......... 1.43 caliber Weight.. 252gr BC......... .378 SD......... .225 Twist..... 1:29
Looks like it can be done.
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Post by edge on Apr 26, 2011 11:56:44 GMT -5
I assume that the T5 is a 5 Caliber tangent radius.
If that is so then your meplat would be 0.258 and there is no way the BC is that high!
Something seems wrong. A 2 caliber radius would give a zero meplat if my math is correct.
edge.
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Post by rangeball on Apr 26, 2011 13:13:57 GMT -5
On the excel program for meplat diameter I'm entering zero. I assume this would calculate for a pointed tip?
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Post by edge on Apr 26, 2011 14:43:11 GMT -5
That gives you a nose length of 0.872 and a bearing length of 0.228 is that correct?
edge.
We are talking about a 40 caliber bullet correct?
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Post by edge on Apr 26, 2011 14:59:09 GMT -5
Here is my math:
OAL = 1.100 your number
If I assume a minimum of 1 caliber bearing length ( 0.400 ) That leaves 0.700 for the nose and a zero meplat means the height of the nose radius is 0.200 ( 1/2 the bullet diameter ).
To calculate the radius of a circle you need to know the chord and the height.
The chord will be double the nose length of 0.700 or 1.400 inches.
R =( C^2 + 4h^2 ) / 8h
C^2 = 1.400 * 1.400 = 1.960 4h^2 = 0.200 * 0.200 = 0.04 * 4 = 0.16 8h = 1.600
1.960 + 0.16 = 2.120
2.120 / 1.600 = 1.325
Nose radius is 1.325 inches OR 3.3 calibers.
edge.
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Post by rangeball on Apr 26, 2011 15:02:17 GMT -5
I figured out where I went wrong. The data shows the OAL and nose length in caliber. When I did the math to calculate the length of the bearing surface I forgot to convert it from caliber of .7ish to inches, so the BS is too short to be very accurate most likely. Back the the drawing board and a good example of why the drawing board is important. Thanks
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Post by rangeball on Apr 26, 2011 15:54:52 GMT -5
How about this one, again with all lead-
Ogive.... S6 OAL....... 1.1" BS......... 1.03 caliber Weight.. 257gr BC......... .365 SD......... .229 Twist..... 1:29
With a soft lead pointed tip, how fast can you push it without it deforming in flight? Do you think the soft lead pointed tip will expand?
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Post by rossman40 on Apr 26, 2011 18:31:44 GMT -5
I wouldn't go sharp point with lead, more chances of it getting damaged. You have to remember a flat or hollow meplat of less then .17 calibers supposedly has no effect on BC. If you radius it you may be able to get away with more and shorten the nose. This basic design was J.C. Postells secret weapon at the Seagirt matches when the Georgia boys whipped on them yankees in the late 1800s early 1900s. The design is still carried on, Lyman produces a mold that BPCR shooter Ron Snover came up with, I do think this BC is a bit inflated but this is one kick butt bullet out of a 40-65 or 40-72 for long range.
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Post by rangeball on Apr 28, 2011 11:03:17 GMT -5
Thanks. I had asked Veral Smith a few follow up questions concerning a soft lead pointed tip at the speeds we're looking to push them, and here's what he said-
He can only do a few ogive radiuses, and I'm not sure he can go as long nosed as the last design predicts. I've given him the bearing surface length and have asked him how long his bullet would be with his longest nose and what it would be expected to weigh.
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Post by rossman40 on Apr 28, 2011 22:27:08 GMT -5
You can look at Brooks molds and maybe talk to the guys at NEI. Dr. Gunn worked with NEI a lot back in the days. Him and Ron Snover were big into BPCR shooting and used the 40-65, 40-72 and IIRC there was a 40-82. Even though these were about the last bullets designed for BP a lot of shooters still shooting them use 5744 and 4198. I think there was the 40-70 and 40 -90 Sharps as well
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Post by rangeball on Apr 29, 2011 8:46:39 GMT -5
Thanks for the leads, I'll do some googling
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Post by rangeball on Apr 29, 2011 13:13:33 GMT -5
I have sent emails to both Brooks and NEI.
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Post by thelefthand on Apr 30, 2011 23:40:15 GMT -5
I'm a little late, and I don't have a vested interest in this since I'm not shooting a 45 barrel, but if you come up with a design that you like you may want to contact HAWK bullets. A few years back, one of the guys got with them (maybe it was Tar, but I can't remember now) and had some made. Several of us went in on it to get the deal to go through. These were all 45 cal bullets to be used with sabots in our 50 barrels. Anyway, the terminal performance was pretty good, but most of us had a hard time getting them to shoot well. I believe it was because we had the jacket thickness spec a little too thick (I believe we went with 0.035"), and they didn't want to obturate correctly. I think I still have a few of them. Anyway, if you come up with a design that you want, those guys may be able to crank some of them out for you. I believe they use Corbin swaging equipment to produce everything.
Mark
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Post by 500cadillac on May 2, 2011 1:02:53 GMT -5
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Post by rangeball on May 3, 2011 8:57:02 GMT -5
Thanks fellas.
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Post by rossman40 on May 3, 2011 9:32:14 GMT -5
I'm sorry to hear NEI went downhill after Walt died a few years ago.
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Post by rangeball on May 3, 2011 9:42:51 GMT -5
Didn't hear back from NEI. Brooks said if I design it they can probably build it, but not much design help. Veral at LBT is checking on a few things to see how pointed he can get and I've sent an email to these guys- www.cuttingedgebullets.com/pages/welcome
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Post by rossman40 on May 3, 2011 13:45:09 GMT -5
After serious pondering on my porcelain throne this morning I have came to this idea. Why spend big money on a custom mold for a experiment. Just go shopping for a used single or double cavity mold like in a .38 pistol bullet and re-cut the mold. Your not putting lube grooves in so chucking it up in a independent 4-jaw and using a custom ground reamer or a boring bar isn't that hard. You can pick up used molds with handles for like $30 or less. Once you figured out what works then go with a custom mold.
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Post by rangeball on May 3, 2011 14:25:56 GMT -5
After serious pondering on my porcelain throne this morning I have came to this idea. Why spend big money on a custom mold for a experiment. Just go shopping for a used single or double cavity mold like in a .38 pistol bullet and re-cut the mold. Your not putting lube grooves in so chucking it up in a independent 4-jaw and using a custom ground reamer or a boring bar isn't that hard. You can pick up used molds with handles for like $30 or less. Once you figured out what works then go with a custom mold. I like the way you think, a cheap bas, er frugal person like myself
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Post by fireevangelism on May 4, 2011 4:43:21 GMT -5
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Post by rangeball on May 4, 2011 8:46:43 GMT -5
Ok guys this is getting interesting. Buddy Al sent me a youtube vid link yesterday of a brass bullet being machined on a swiss type lathe. At the end of the clip it said it was produced by cutting edge bullets. I googled them, found their contact info and sent the following email message, to which they responded. I have their permission to update you guys, but I'm excited that progress can be made- I'm out of the office for work most of the rest of the week, but plan to try to call him Friday. Sounds like they are very interested in helping us out. No idea yet what the final cost might be, sounds like more than a barnes, but if they work there should be nothing else like them out there. I'll keep you posted
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Post by edge on May 4, 2011 9:10:11 GMT -5
Just to be clear he is offering you a Copper bullet and not the Brass bullet you described in the video. " . Also, since the copper we use is much softer than the Barnes Gilding metal, expansion is going to be awesome" I am not arguing an advantage of one over the other, just clarifying what they are offering you edge.
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Post by rangeball on May 4, 2011 9:20:55 GMT -5
I understand and should have made that clear. In my mind copper is superior to brass, other than cost of course
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Post by edge on May 4, 2011 9:22:32 GMT -5
SNIP. other than cost of course ;D ;D ;D
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Post by rossman40 on May 4, 2011 10:55:53 GMT -5
Fireevangelism,, The 405 Winchester is the closest modern centerfire to what we are trying to do with a .40 ML bullet. The problem is it is .411 and resizing it can be done but the only jacketed bullets available follow the original weight of 300gr. The 405 Win was the bad boy in it's day for lever actions and stayed at the top till the 444 Marlin came out in 1964.
When resizing you should do it in steps of like .004" but the big problem is when you squeeze it down the copper jacket likes to snap back a thou or two so you can end up with the lead core being loose in the jacket.
I think we are following the steps of early long range target shooters. They went from the early Sharps and Remington buffalo rifles in .45 and .50 and then started going smaller to .38 and .40 around 1880 which you see in rifles like the 1885 Winchester/Browning and the 1876 Marlin/Ballards. To bring it to modern times the White Rifle factory team smoked everyone at the 2006 Friendship, IN matches setting new records with .36 cal rifles.
While guys shooting the .45 using sabots with .40 200gr bullets are doing well the optimal bullet may be a tad heavier. We know the sabotless .45 250gr shoots pretty good, would a saboted .40 225-250gr do as well? I think that is where this line of experimenting is going.
The key to the mono-metal bullets IMO is going to be the annealing. Copper may be optimal but from my research your better off turning it hardened and then annealing it. Then for a hunting bullet juggling the size of the nose cavity.
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Post by rangeball on May 6, 2011 10:29:54 GMT -5
As soon as a machine opens up cutting edge is planning to run 36 bullets for testing. He is asking if we want the base radiused to match the harvester blue sabot. I told him flat works best, but would check with you guys to see what is preferred.
The .40 XTP base seems very flat to me, and it's a proven performer in a sabot. The new barnes base is almost as flat. Is there any merit in the base being radiused to match the sabot? I'm leery of anything but an almost flat base, but defer to the experts.
As soon as we have a good feel for this I'll get back to him and hopefully this will move forward very soon.
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Post by fishhawk on May 6, 2011 10:43:41 GMT -5
I would think it needs a slight radius to avoid having a sharp edge that can cut the plastic. I wiould match it to the Barnes or XTP.
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Post by dave d. on May 6, 2011 11:33:44 GMT -5
I know to much radius is no good but I would think if the base of the bullet matched the bottom of the sabot perfectly there would be more contact surface which might be a good thing. If its not to much trouble why not make a couple of each design for experimentation. Hey But What do I know I'm just a dumb ironworker ;D.
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Post by rossman40 on May 6, 2011 11:38:15 GMT -5
I would have to agree with Fishhawk, a slight radius to avoid sharp edges. What is the radius of the bullets compared to sabots? I do not have any bullets or sabots on-hand to put on a optical comparator.
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