Wrt to propellant selection, I have read of some folks trying to minimize recoil by selecting powders with lower charges to reduce the "propellant ejecta" component of the recoil equation. I question this as being sound logic UNLESS the burn profiles fit - ie. going to a faster powder that uses say 100 grn vs 125 to achieve the same velocity. The bullet's velocity may be the same in each case but the perceived recoil I would (from experience) think would be much different as I've seen in shooting a friend's .50-110 Win. We put together some 450 grn cast loads that were pushing the same bullet to the same velocity but with propellants of differing burn rates. I remember the 3031 loads would bust your shoulder farily quickly whereas the slower propellants were a nicer "push".

I'm interested in hearing from others that have "rung this out" in their big bores - especially the 50 cal cartridges. I will hopefully be experimenting with these in my 50 Alaskan in the coming year.

Any comments?

Jeff Pfeifer

Pfeifer,
This is a question that comes up a couple of times a year. Saeed had requested everyone's recipes for reduced loads. Probably still collating.
Use slow powders: H-5010, H-1000, H-870, RL-22 and 25, XMR-8700 and IMR7828.

Very simple procedure: Fill case so a seated bullet lightly compresses the powder column and you are good to go. Use a really hot primer like the Winchester Large Rifle Magnum though not critical.

For the .500 A-Square with 600 grain bullets:
IMR-7828 115 grains ~1750fps 110grains 1450
H-870 122 grains ~1800fps
RL-22 112 grains ~1900fps 125 grains 2200
H-4831sc 110 grains ~2150fps

XMR-5744 with cast bullets is fantastic, 35 grains with a 575 grain cast, lubed, gas checked bullet gives 1100fps and makes the funniest sound, like a loud TOINK!

H-5010 I cannot recommend as it does not develope enough pressure to adequately seal the chamber, velocity around 1050fps almost subsonic.
H-1000 is dirty, leaving much unburned powder but if you do not mind extracting your cartridge case with muzzle down and blowing into breech to clear particles it will give you around 1250fps. I have been on receiving end of some strange looks at the range as I cleared the barrel of particles by giving a good puff into the breech. I could care less. I was having fun and they weren't.
Hope this helps.

Roger,
WRT the 500 A-Square loads - any powders "feel" any more comfortable to shoot that the others and still give decent accuracy? In the .50-110 loads we were playing with the 3031 is noticibly different.

I'll have to try some XMP-5744 at that velocity! Does this powder prefer a magnum primer or will a F-210 or WLR do OK?

JP

My only experience on this is in the opposite direction. When I had my 458 lott, I worked up max 500 gr loads with RL15, and was getting 2280 fps from the 20" barrel. I then decided to try VV N550, figuring it was really too slow for the application, which proved out, but hey, I was curious. What I did note is that while the velocities were just shy of 2200 fps, the 8% higher by weight load had noteably more recoil then the 100 fps faster RL 15 load.

Now, if you really want to reduce recoil, use lighter bullets! When I fired 350's from the lott, it was a pussy cat, 500's, it was a tiger.

For the 50 Alaskan, I'd go with the powder that produces the best accuracy. I would guestimate that with 400-450 gr bullets, that Reloader 7 would be a good choice, has worked well for all applications it was appropriate for in my limited experience. When I get my 50 Alaskan someday, RL7 will be my first choice for the 450 gr cast bullets.

I don't know about reduced loads, but in the 500 and 577 NE. IMR-4350 gives a substantial reduction in recoil over IMR-4831 at the same velocity....

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Ray Atkinson

ray@atkinsonhunting.com
atkinsonhunting.com

You know guys I have absolutely no idea how I made the grades I did in Physics! OR, the rules of physics seems to have changed sense I went to school.

A bullet of a given weight, fired from a rifle of a given weight,at a given speed, will cause the same reverse thrust, no matter how it is made to gain that speed! CASE CLOSED!

The reverse thrust can be built up over a longer period of time by the selection of a different burning rate, makeing it seem the recoil is less, while it is not! The feet lbs of recoil will be exactly the same,at exit, but the percieved reverse thrust will be different. This is the reason for some chamberings to seem to have more recoil, like the hot 30s which build their speed in a shorter time than a big bullet's slower build up of speed. This is what some describe as "SNAPP",for the shorter time build up, but these two are usually exiting at different speeds, and the weight of the bullets are different.

In any case what you feel is what you are trying to change, so if the perception is what you are looking for it will work. My question is why? If the recoil of a particular rifle is more than you want, the simple selution is to go to a different rifle/chambering! BUTTTTTTT then that's why there is more than one flavor, because people do not all want the same thing! Though they may taste different they are both still chewing gum! PERCEPTION!

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..Mac >>>===(x)===>
DUGABOY DESIGNS
Collector/trader of fine double rifles, and African wildlife art

Mac,

You are leaving out the jet effect of the powder gasses in the barrel when the bullet leaves the muzzle. The gas pressure at the muzzle tends to dominate the recoil component of the gas jet.

That's why I try to pick a faster burning powder if I'm not going for the ultimate in velocity - you use less of it and you have a lower muzzle pressure. Both factors tend to lower the total recoil.

Don

Felt recoil is not so much associated with recoil energy or recoil velocity but with the recoil acceleration. The jet effect is only for 20 %.

Don G has the truth of it--the gas volume is dependent upon the charge weight of course, and the more the volume, obviously, the greater the muzzle pressure. For something like the 50-110, R7 as was mentioned would be a good choice. You may even want to mess around with REALLY fast powers, like IMR 4198, 4227, etc, but be careful as small increases of such explosively fast burning powders will not allow as much mistake on the high end. If you really want to find out what to try, get Neco's Quickload--it's pretty nifty.

Please educate me. I can buy the idea that a faster burning powder and a therefore a smaller charge will have less to be still burning when the bullet leaves the muzzle.

But as this all happens in a few hundredths of a second, can you really feel the difference in recoil? I admit that shooting a 300 WBY is a painful experience compared to other calibers of equal muzzle energy, but is this why?

Pfeifer,
My favorite powder for the .500 is IMR-7828. I use it because it is clean. You can use any of the other powders but some of the ultra slow Hodgdon will leave unburned powder particles in bore.
The XMR-5744 was designed for the cowboy action shooting with cast bullets.
My rifle has a 1-10" twist and gives excellent accuracy with all the bullets and powders I have used.
Roger

Will,

QuickLoad has a recoil calculator that shows the recoil due to the acceleration of bullet and powder/gasses within in the barrel. There is not much you can do about that portion of the recoil for a given muzzle velocity and bullet weight.

QuickLoad gives a separate answer for the Total Recoil Values at the end of the Gas AfterEffect. This is 20-30% of the total. This is the recoil you have a chance do something about by choosing powders and muzzle brakes.

Simply by choosing a different powder you can easily save 6% on the total recoil at the same muzzle velocity. Of course if you are after the last 50 fps you are forcd to a slower powder, with higher gas presssure at the muzzle and consequently higher recoil. You pay two or three times in recoil for that last 50-100 fps.

See the link below for a long and labored discussion!

Powders, rocket effect and recoil

Don

[This message has been edited by Don G (edited 07-10-2001).]

As Don says, if one is looking for every bit of speed he can get, he is compelled to use certain powders. If one has a certain velocity in mind and that velocity is within the safe capability of the cartridge, he can opt for a faster burnrate and reduce the total charge weight. Using RL-15 in the .505 Gibbs I achieved the desired velocity while burning 17% less powder than with IMR-4831. Doing so, provided a marked difference in the "shootability" of the rifle and such was reflected in better average groupings.

Nickudu,
Thanks for your comment. My friend Paul should be getting his .505 Gibbs on a P-14 sometime this year. He'd probably be very interested in comparing notes with you! Jim Wisner gave him some good reloading notes from his .505 Gibbs "experience" to start with and I know that he has been collecting data from other sources as well.

Guess I may have had the powder rates twisted around in my head as to which gave the push - the slower or faster powders. I remember IMR 3031 though was the shoulder "fatiguer".

I remember reading a fascinating article sometime back about the development of the PPC cartridges and how Farris(?) Pindell had the barrels instrumented looking for lowest exiting pressure at the muzzle (I think) such that when the bullet left the muzzle it was minimally disturbed by the exiting "gas jet"...Looking for best accuracy in this case. A different goal than looking for reduced perceived recoil but somewhat related. I'm an electrical engineer by degree so this is all good fun stuff to my way of thinking...Another quest for understanding.

Regards,
JP

Pfiefer,
Permit me to clarify something. My posting refers to the circumstance of loading for a < than maximum velocity in a given case.
I believe the reduction in felt recoil, or the increase in rifle managabilty (however one wishes to express it)is attainable via the use of powder with a faster than usual burnrate.

When loading for > maximum velocity in a given case @ equal pressures and bullet weight, the powder with the faster burnrate often seems to intensify or sharpen recoil IMHO. This, perhaps, bears out your observation as to the IMR 3031 loading (?).

I do not profess to know the why and how of it. I can only convey to you what I perceive to be valid from my experience.