does anyone know or can speculate on the low end speed for this bullet to expand?jackfish and others may know....i think it was posted awhile back on the old marlinowners site....thanks in advance...bearit....

I'm not sure it expands at all at factory velocity (1200 fps from a ported 18-1/2 inch tube), at least on whitetail. Of course, for most work a .458 flatnose 405 doesn't need to expand to get its work done...

My grand total is one caribou with this bullet. I launched it at 1750 out of a 450 Marlin and it certainly did expand at 75 yards (1450-1500ft/sec) The wound was devestating and the core separated....the jacket weighs only 50 grains or so so consider this a hard lead sabot in a light discarding jacket. Penetration was excellent as the bullet quartered through the back ribs and was found under the skin of the shoulder on the far side. The jacket stripped of on the shoulder bone. A picture of it has gone the rounds as an example of it's failure but it worked well enough that I used the same load when hoping to run across a moose this season.

I doubt if you would get much expansion at 1200 or less but as pointed out it wouldn't matter much.

bearit

If you want expansion at low 45/70 velocity try the 400gr Speer.

I am a 45/70 shooter and in all the tests I have seen it gave the best performance at lower velocities.

I use this bullet exclusively. When I was developing loads, I pushed it close to 2000fps and discovered that it was too soft for that speed. I eventually settled on 1700-1800 fps range as about right. It drops my Elk nicely expanding out to nearly an inch and plowing through large bones. But it will shed the jacket and there's a generation that feels that is a problem. For them, there are many $2 bullets to choose from.

Remington loads the 405gr jsp to about 1200fps out of a 18.5" barrel. It will just barely expand on game unless it smacks a bone. Deer hunters using this load report complete pass-throughs and no recovered bullets. My guess is that the striking velocities are close to 1000fps.

I don't know the alloy, but the Rem is not a supper-soft lead. It is also not super hard. I would guess that it is about 15bhn - not hard enough to fracture and not soft enough to splatter.

quote:

Originally posted by dla:
I use this bullet exclusively. When I was developing loads, I pushed it close to 2000fps and discovered that it was too soft for that speed. I eventually settled on 1700-1800 fps range as about right.

How do you crimp them? Do you find a case-filling load to prevent bullet setback in the magazine?

I use the Lee Factory Crimp die and crimp very hard. But most of the holding tension actually comes from the sizing operation. So in my experience, sizing is more important than crimp for "setback". And crimp is more important than sizing to prevent "backout".

I personally think it is very important to check for setback when shooting something lightweight like the Marlin Guide Gun. Take a shot and then measure the 2nd round in the magazine.

I neck-size only. I thought my crimping would overcome lack of sizing, because my loads would pass a 2' drop test. But then I did the "shoot and measure" and discovered I was getting setback.

The 405gr Remington needs about .7" minimum bearing surface to hold and given that the 45-70 case is tapered, 0.7" is about all you're going to get whether you full-length or neck resize. Just letting you know that you can reload faster and with less mess by going to neck resizing.

Cast bullets, and bullets with correctly placed canelures can be crimped to hold - especially using the Lee FC. But the Remington needs a combo of good neck tension and good crimp. By the way, nickle-plated brass is more "slippery" than plain brass, so much of my experience was with NP brass.

I don't use powders/loads that compress. I use 43.5grs of H4198 which fills ~70% of the available space.

thanks for the responses....i shoot these 405's at 1900fps to start and i wondered how far out they would expand....i'm guessing about 150yds or so......thanks....bearit.....