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bishopgrandpa
05-22-2019, 10:06 AM
How hard can a cast HP boolit be and still be expected to open? From a 44 I will be using a 240 gr at about 1200 fps. A one lino to one pure lead should give me approx. a 13 BHN I figure. Will this be to hard to be expected to open on whitetail deer. Have yet to try on water jugs but that isn't the same as in the woods.

kir_kenix
05-22-2019, 10:27 AM
I think it's going to depend just as much on the hp design. Shape, depth, diameter, etc. I think you won't have a problem, assuming your impact velocity is above 1,000fps and your hp cavity is large enough to displace some material. Maybe post a pic and specs (boolit #) of your projectile and somebody will have some reliable data.

RogerDat
05-22-2019, 11:10 AM
With a gas check design maybe you could go a little lower hardness? I would also wonder about using Powder Coat to allow for a softer alloy? I don't load HP for the 44 mag but both gas check and PC have allowed me to go softer in rifle calibers.

Larry Gibson
05-22-2019, 11:16 AM
The BHN is actually not relevant. What is needed is malleability. The Linotype, even though "watered down" with lead, has entirely too much antimony for reliable controlled in game expansion at 1200 fps muzzle velocity. If it expands at all most often it is not expansion but the shattering or tearing of the HP portion of the nose off.

Over years of experimentation with HPs in rifles and handguns with cast bullets, after tests in various media and actual game shot I've found a binary alloy of lead + a small amount of tin works best for velocities below 1600 - 1700 fps.

In the 44 magnum a 240 gr PB'd can be bulled accurately to 1200+/- fps out of 4 - 6" barreled revolvers when cast of 20-1 alloy. The same bullet can be pushed up into the 1400+ fps range when cast of 16-1 alloy. Both will give reliable expansion in game within reasonable range with a proper sized HP. If the bullet is GC'd then a 30 -1 or 20-1 alloy can be used across those velocity ranges.

For HP cast bullets in revolvers a 40-1 alloy works well up through 900- 1000 fps and a 30-1 alloy works well in the 1000 - 1200 fps range. Of course those are not hard and fast velocity ranges as much depends on the HP design, the bullet design, whether GC'd or not and the actual load (acceleration rate) used. A good softer alloy such as BAC or a NRE 50/50 lube is recommended.

Over the years I have used numerous 200 to 300 gr HP bullets in my 44 revolvers at 1000 to 1400+ fps. I have settled on the Lyman "Devastator" cast of 16-1 alloy and pushed at just under 1400 fps out of my Ruger FTBH with 6 1/2" barrel. That alloy also works very well at higher velocity out of my Contender and M94 Carbine. If used in my 4" barreled Colt Anaconda I cast them of 20-1 alloy and push them at 1200 fps. It weights 270- 275 +/- gr fully dressed when cast of 20-1 or 16-1 alloy.

242233

bishopgrandpa
05-22-2019, 12:05 PM
Great info. Thank you.

fredj338
05-23-2019, 02:39 PM
I think it's going to depend just as much on the hp design. Shape, depth, diameter, etc. I think you won't have a problem, assuming your impact velocity is above 1,000fps and your hp cavity is large enough to displace some material. Maybe post a pic and specs (boolit #) of your projectile and somebody will have some reliable data.
^^this^^^
HP design is as important as the alloy for reliable, predictable expansion. For 1200fps, I like cup points & softer alloy. I avoid antimony in my HP alloy because ti tends to be brittle. So my HP alloy is mostly just tin & lead, 20-1 or 25-1. Though range scrap with a bit of tin also does well.
I have a Lyman Dev mold, since took the gc off, Got a couple diff pins made. So I can go mild to wild by varying the pin & alloy.
https://img.photobucket.com/albums/v703/fredj338/44-272-1K.jpg (https://smg.photobucket.com/user/fredj338/media/44-272-1K.jpg.html) https://img.photobucket.com/albums/v703/fredj338/44-272.jpg (https://smg.photobucket.com/user/fredj338/media/44-272.jpg.html)

Petander
05-23-2019, 04:29 PM
Very good cast HP read here:

http://www.lasc.us/Fryxell_Book_Chapter_13_CastingHPBullets.htm