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Posted: 3/21/2010 12:49:00 AM EDT
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More specifically, how many FPS are needed to make a given cartridge lethal enough.
I'm referring to popular cartridges that are being worked up for maximum lethality for the users intended purposes. For example here is what I load .45 ACP and .223 are for two legger defense / SHTF 7mm rem mag for large game hunting .44 mag for bear defense when hunting (I only load plinking for my 380, no defense loads) So when I am working a load up for a given bullet in those cartridges (or other popular cartridges), how fast is fast enough? I have yet to get as fast as the manuals say I should, even when using the same length barrels. Some of my load work ups have been well below freezing, so they will have to be reworked soon with spring on us. Let's take the .45 ACP. I worked up a load for Hornady's 230gr XTP w/ 8.0 grains of Accurate #5. It's giving me 800 FPS. Is that fast enough? What about up here in AK where an assailant can be wearing 5 layers (I've seen street people wearing more). What about my plinking ammo that is only about 750 FPS, is that fast enough to use for SHTF ammo if it came down to it? When you are working up a load, how do you decide when to stop? I am working up my hunting round for my 7mm rem mag. I worked very slowly up to the max listed in the barnes manual (150gr Tipped TSX). They say I should get 3015 fps (give or take) and I have been getting just over 2900 at max charge (same barrel length as listed). I plan on stopping there, but before I load up a whole bunch of them, I was wondering if I should try a different powder to get to the 3000 fps mark (using RL 22)? What do you think? |
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for 45 id say around 800 is good
223: 3100 55grain shtf: 3200-3250 44: 1200 240 grain jhp plinking ammo for 45..700fps shtf ammo for 45...800-850 jmo thats just me if the stuff is to powerful you cant hit anything, whats the point!? 
what powders/bullets are you using? |
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One way to check what a reasonable velocity should be is to go to the websites for the ammo manufacturers and look up their published velocities.
Example Remington UMC / 45ACP / 230 FMJ - muzzle velocity is 835. In this caliber I see no point in downloading it. Just load to something close to this velocity. 44Mag for bear - I think here you would be wise to work up something close to a full house load. I would not want to screw around with bears. For fun you can work up a downloaded version at a starting load using something like Unique or even Trail Boss for powder puff loads. |
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With handgun cartridges, you just need enough velocity to get sufficient penetration. The temporary stretch cavity caused by a bullet impact can cause damage with bullets traveling at rifle velocities, but with handgun rounds the TSC is so small as to be insignificant. For 45, 800 to 850 fps with a 230gr bullet should give you sufficient penetration. Your 750 fps plinking ammo would actually work for SHTF and SD if it's the right bullet. At those velocities, a semi wadcutter will still get deep penetration.
For 7mm mag, 2900 fps with a 150gr bullet should be sufficient. I don't think that extra 100 fps will make a whole lot of difference. Then again, there's nothing wrong with experimenting with other powders and loads, as you may find something better. In any case, at that velocity, a Barnes TSX is going to cause helacious damage to it's target. The TSC will cause serious remote wounding effects in soft tissue, and the bullet will cut a large permanent cavity as well as crush any bone it encounters. I consider that load sufficient for all game up to Elk size, and can be used for Moose at short range if needed. It can be used against brown bear if necessary, but I consider 7mm too small of a bore in any cartridge for bear hunting. For 223, if you're shooting 55gr FMJ, a muzzle velocity of 3000 to 3200 fps would be for the best. Truth is, for SHTF, I'd prefer a commercial hunting bullet to OTM or FMJ. I'd look at a 64gr Winchester soft point; you should be able to drive it up to around 2800 fps, and it will have good, consistent terminal performance over most of the cartridge's effective range. |
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First off, you usually can't reach published bullet speed even using factory ammo. Those speeds are reached in ideal settings and circumstances. Temperatures where you are at will have a significant effect (among a host of other factors ie. bbl length, chamber etc). Second, how fast is fast enough depends on what bullet you are using. Bullets will not expand or fragment below certain velocities, but it depends on what bullet you are using and how it was designed to be used. Most SD/HD bullets are designed to fragment at reasonable any speed. Third, velocity is/should be lower on the list any given loads priortity. It should be
1. safety...is it a safe load 2. accuracy...for obvious reasons 3. velocity...as much as possible without affecting 1 and 2 Your velocities are fine. |
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High speed expands the effective maximum point blank range to longer distances, which reduces errors due to range estimation.
Large diameter heavy bullets at low speeds coupled with shot placement are deadly. Even light bullets at not so fast speeds are deadly with shot placement. I think that bullet construction becomes more important at high speeds and has to be matched to the application more carfully - a bullet for tiny varmints is a poor choice on a white tail if it is shot at high speed. In the 50's, PO Ackley and a couple of other men were experimenting with .17 caliber rifles and shooting damn near everything in sight including large hoofed animals, reportedly with great success. But then the .17's nearly died out. We can speculate on the reasons, and I expect there are two or three. If someone breaks into my house and the closest ammunition I can get loaded is a 130 grain round nose FMJ bullet running at standard .38 Special velocities or .45 ACP ammo with 200 grain LSWC's loaded with 3.8 or 4 grains of Bullseye, or even a magazine full of CCI Stingers in a pistol, that's what I'll use and I'm not going to get too tied down worrying about their efficiency in killing an intruder. Quoted:
First off, you usually can't reach published bullet speed even using factory ammo. ... That's an interesting comment, and it is simply not true enough (often enough) to make that broad statement. |
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how many FPS are needed to make a given cartridge lethal enough
Enough that that bullet is within it's expansion threshold and will open enough to give proper terminal ballistics. This information is often available from the reloading manual. The Ammo Oracle has a discussion on .223 Remington proper terminal velocity. With a slow round like the .45 ACP that is already on the threshold of too slow, velocity is more critical. Once again, reloading manual data is the best source. The good thing about .45 Auto is that it's reputation was built on RN ball ammo, so even if your XTP doesn't expand, at worst it will duplicate RN military ball performance. Stuff like the little 9mm Luger is much more critical, because RN ball ammo in it does not have the same good rep. With your 7mm Mag you don't say what powder you are using. In Alaska I would certainly use a powder that is listed as being temperature insensitive. This usually means that they are temperature insensitive to cold. RL-22 is a great powder and absolutely one of my favorites for stuff like the 7mm Mag, but it is not a temperature insensitive powder. You will certainly lose velocity when its very cold with it. 100+ fps could be very likely. So it might not be the best AK powder. Powders on the order of H-4831sc or Ramshot Magnum are temp insensitive and probably would work very well - especially when you are working up in the cold. The other issue with loading for the 7mm Rem Mag is that, unfortunately, there is a whole lot of variation in actual chambers specs with this round. This is because manufacturers can let the chamber specs get sloppy because it headspaces on the belt, not the shoulder. A look in several reloading manuals shows maximum load data to be all over the map. So it is very difficult to get a good handle on what to work up to. In my own experience this certainly was true, and using a 150-gr bullet and RL-22 I ended up where you are (but in warmer temps) with my work-ups based on what I could derive from the manuals. Of course the load is still lethal, but it is closer to what I consider a .280 Rem load than a 7mm Mag load. Normally the reason hunters buy a 7mm Remington Mag is to get 7mm Remington Mag velocities. Sounds simplistic, but it's true isn't it? So you want to get factory ammo velocity anyway. Since you can chronograph your ammunition, I would suggest for the next go-around that you get you hands on some 150-gr factory ammo and chronograph it from your rifle. Unfortunately Federal Premium on lists 140 & 160 grain TSX loads or else you could use the exact same bullet. Then work up to the velocity + or - 50 fps of what the factory stuff chronographs. This will give you a safe load. You might want to think about changing to 160-gr TSX bullets too. This is the most popular heavy big-game weight for 7mm Mag and you can use the Federal Premium load to give you an exact idea of where to work up to with the same bullet. In addition, I would also go the factory ammunition chronograph route for your .45 Auto and .223 Rem loads. In .223 you shouldn't attempt to reach the same velocity as 5.56 NATO (3240 fps for 55-gr & 3100 fps for 62-gr) but should stay 50 to 100 fps less. Depending on your rate of twist 69 to 77 grain OTM match bullets are considered to be the best self-defense loads. I wouldn't exceed 2850 fps with a 69-gr HPBT Match bullet in a 20". I've never chronographed 77-grain OTM bullets, so I'm no help there but If you see what actual ammunition is doing in your guns, and you work up to this velocity level (watching for pressure signs of course) you will never have an over-pressure issue and will achieve all that can be done with your gun/caliber. Why is chronographing factory loads from your guns the best route to get a handle on load work-up goals? Because: "Muzzle velocity for a selected load is a function of the mean effective pressure and the barrel length."
Lloyd E. Brownell, Ph.D. - Firearms Pressure Factors, Wolfe Publishing Co. ...next to real pressure equipment, a chronograph is the best guide to excessive pressure for the home handloader. There are no “magic barrels” that allow another 100 to 200 fps!
Handloader, June 2004, “More Pressure Experiments” (Reading Chamber Pressure), John Barsness. My yardstick for pressure is a combination of chronograph readings and primer pockets... The speed readings are easy: don’t expect to get much more or much less than what you see published, and pay close attention to the rifle barrel specs the data came from...
GUNS Magazine, May 2010, “Reloading Puzzles & pieces thereof”, Glen Zediker See also the web page here on AR15.com "Best Choices For Self-Defense Ammunition" where the following.223 ammo was recommended - and easily duplicated by reloading in the order of preference: Black Hills or Hornady 75 gr OTM Black Hills or Federal 77 gr OTM Black Hills or Federal 69 gr OTM Black Hills 68 gr OTM Winchester Supreme Power Point Plus 64 gr JSP Federal 55 and 62 gr Trophy Bonded Bear Claw (these also penetrate deeply, even through barriers so be careful where you employ these rounds) Black Hills 60 gr SP |
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Quoted:
First off, you usually can't reach published bullet speed even using factory ammo. Those speeds are reached in ideal settings and circumstances... . I think that any reloader should understand "published speed" vs. actual speed. Anyone with a chronograph that has used it much knows that published speed is often a bit unrealistic and often high - or as you put it - shot in ideal circumstances. An example would be .223 Rem SAAMI-spec 55-gr ammo from Remington, which shows a velocity that is the same as 5.56 NATO-spec 55-gr Lake City, but in real life is 150-200 fps slower. Or .30-06 150-gr published specs of 2910, that can be as much as 100 fps slower when chronographed in actual rifles with the common 22-inch barrel length. So yes, is may be unlikely that you can reach the published speed of factory ammo like this, but if you shoot factory ammo from YOUR rifle and chronograph it, it normally is very reasonable to be able to duplicate the speed that factory ammo gives you from YOUR gun without any excess pressure involved using powder of the optimum burn rate. The only exceptions to this would be the newer factory ammo types like Hornady Light Magnum loads that use a special powder and reloading technique unavailable to us home reloaders. It is also very reasonable to be able to duplicate reloading manual velocity, generally speaking, if you take into account the barrel length that they use in their data. No, you can't usually get the speed that they get from a 24 or 26 inch pressure barrel because usually your barrel is shorter, but if you take into account the loss of velocity that occurs when a shorter barrel is used, then you can come very close. Some data sources, like Speer, re-shoot the pressure-barrel-developed data in real guns with normal barrel lengths to give you a more realistic velocity. Others re-shoot some data, like .223 Remington in an AR15 and put that in a special section. That velocity is usually easy to reach safely with a 20" AR15 with proper powder choices. When it comes to handguns, the published data velocity is much easier to achieve with handloads. Factory ammo usually chronographs much closer to spec in handguns as well. I would guess that this is because velocity is more of a selling point in rifle HUNTING rounds than in handgun rounds. Factories have known that velocity sells in hunting rifle cartridges ever since 1915 when Savage decided to go with a 87-gr bullet in their new 25 caliber round, the .250 Savage because it would achieve the magic 3000 fps number rather than the slower 100 grain bullet that was the original development. The "250-3000" moniker sold a lot of Savage Model 99s in the day. The same is not so true of handgun rounds, except in the case of the original .357 Mag loadings, that have been reined in - in later years. I think because handgun rounds are much lower pressure rounds and are shot in such short barrels, that specs are pretty close to real-world. Once again, chronographing factory handgun ammo in your pistol shows its real-world velocity, and normally can be easily duplicated with safe handloads. Some of the newest rounds, like the WSM cartridges, from my tests with a .270 WSM and Winchester factory ammo, actually chronograph from a 24" barrel within a scant few feet-per-second of listed factory ammo velocity, unlike older established rounds. You can duplicate this velocity close enough to say it has been reached with the proper powder choice, but I definitely wouldn't exceed those factory velocities for obvious reasons. So to sum up - discrepancies in velocity between published data and actual data do exist. One must take into account the barrel length and tight chamber of the published data (ideal circumstances) and deduct a bit from that. One must realize that specialty loads like Hornady Light Magnum cannot be duplicated as to velocity. The best way to find actual velocity data is to chronograph factory ammo in your own guns. This real-world velocity can normally be achieved within safe pressure limits because as Lloyd E. Brownell, Ph.D states: "Muzzle velocity for a selected load is a function of the mean effective pressure and the barrel length." Therefore if we do not exceed factory velocity as measured in our own guns we do not exceed factory pressure as long as we are using a powder in the proper and optimum burn range. Handgun ammunition and published specs are much more realistic than most rifle rounds and once again, data velocity, both published as as actually shot can normally be replicated with handloads without any pressure/safety issues as long a proper bullet seating depth and powder burn rate is used. . |
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Quoted:
First off, you usually can't reach published bullet speed even using factory ammo. Published speed is often from test barrels and not real guns. When the data is from real guns, it is usually pretty accurate IME. I've got 22-250 ammo that claims 4k+ fps on the box and has met that(and exceeded it slightly) from two very different rifles. |
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Wow, thanks for all the replies, I have a lot to think about.
Here is what I have worked up. .45 acp 230gr HDY XTP - 8.0 gr AA#5 for right at 800fps. 185gr Berry's plated HBRN (plinking) - 9.0gr of AA#5 for around 800 fps 230gr Berry's Plated RN (plinking) - 7.0 gr of Ramshot True Blue for 750 fps .223 69gr Sierra MK BTHP - H4895 25.0 gr for 2860fps (does that fps make sense? my chrono was acting up) 68gr HDY HPBT - Varget 24.5gr - for 2600 fps I'm getting ready to rework all my .223 loads as I just ordered a 1 in 7 twist barrel (have 1 in 9 right now) - I want to load up the heaviest barnes TSX I can for my always loaded SHTF stash and for deer (maybe) - I just set up a load workup for HDY 55gr FMJBT w/ Cannalure using Ramshot TAC, haven't shot them yet. .44 Haven't worked up any hardcast lead bullets yet - Also, I shoot a S&W airweight so my loads are just this side of heavy - 240gr HDY XTP - Win 296 23gr for 1175fps - 240gr HDY XTP - Ramshot True Blue 13gr for 1140fps - 240gr Berry's Plated HP (Plinking) - Ramshot True Blue 11.5gr for 975 fps - 240gr Speer GDHP and GDSP - Win 296 - 23gr for 1175 fps |
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