OzarkPA

Based off of some suggestions here, I'm using 250gr .45 speer gold dot / deep curl bullets with harvester CR sabots and 90gr BH209. I have a ballistics calculator on my phone that I was messing around with and the way I have it sighted in (2.75" high at 75) and estimated 1820fps shows me a +/1 5" hit out to 174 yards. After that's all said - is there a way to estimate how much fps / fpe is needed to get the bullet to perform properly (expand and exit the other side of the vehicle or just stop short of that)?

sabotloader

This might give you a ball picture

lemoyne

The accepted minimum on deer in FPE is 800 FPE on Elk I would want 1000. There have been a lot killed with less but that is chancy.

OzarkPA

Thanks - that's good for a new guy like me to have a ball park idea. I was thinking I read that somewhere too. Considering that, I was trying to google for the answer to my question and came across this http://www.gunblast.com/RKCampbell-GoldDot.htm website and it listed the gold dot .45 with 765fps from a handgun with 14.5" penetration, but not sure if that would be enough for a deer or not. I was just interested to see if those longer shots, IF possible, would be ethical (enough fps to allow the bullet to function properly with enough energy for the intended target to cause a quickly fatal wound).

Semisane

Starting at 1800 fps from a rifle, that 250 grain Deep Curl is still moving at over 1100 fps at 200 yards. That's a few hundred fps faster than the muzzle velocity of Remington's and Winchester's 250 grain .45 Colt factory load when shot from a 6" revolver. Speers' factory load for the 250 grain DC yields a muzzle velocity of around 750 fps from a revolver.

I would suggest that any deer shot at ten feet with a revolver and a 250 grain Speer, Winchester or Remington factory load is going down pretty dang quick. The same holds true at 200+ yards from a rifle.

HEAD0001

When you are dealing with big heavy bullets the FPE is not as important as it is for the sub calibers. That is why so many Bison fell to 400+ grain bullets from the 45-70 at 1200 fps. Those big bullets do alot of damage. Regardless of how much energy they put out. Heavy bullets are just different.

Did you see anything published from Speer saying what the minimum velocity is for expansion of the Deep Curls?? I am going to give the 300 grain Deep Curls a run here in a couple of weeks. The bullet should be devastating, even if expansion is minimal. Tom.

Semisane

I haven't seen anything like that published by Speer HEAD. But I think it's fairly safe to make some assumptions.

The 250 grain DC is designed top expand at .45 Colt handgun velocities, where the normal muzzle velocity is 700/800 fps and even a very hot load is under 1000 fps. So I would expect it to expand at very low velocities, probably down as low as 500 fps. However, we have good evidence that it won't fragment and holds together beautifully at whatever velocity you can push it.

The 300 grain DC is designed for the .454 Casull handgun round, which claims a muzzle velocity of 1600 fps. So I would expect expansion down to 800/900 fps (probably lower). It too will hold together as fast as you can push it.

lemoyne

My own experiments tell me that you do get reasonable expansion down to 900 FPS.

OzarkPA

So... as HEAD mentions - that 900 fps is well below 700 fpe, but since the bullet should perform then the deed should still be dealt, I figure. Cool part about ML is someone with a chrono should be able to see how low can you go on the charge to get the magic mushroom.

oldsmellhound

I think the better question if you are talking about shooting at ranges that long is related to bullet drop and wind drift. I would be pretty confident that the load you are describing would cleanly take a deer at 200+ yards IF the bullet is placed properly. The trajectory of that bullet drops off pretty fast at those ranges, and wind drift might be measured in feet instead of inches if you have a good crosswind....