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I'm going to buy 500 rounds of .45 ACP FMJ to start shooting USPSA. I'm thinking the 185 gr will be better because of lower recoil. I've only shot 230's. Is the recoil noticeably lower? Or are the affects noticeable by the end of the match? I'll be shooting the full size M&P that eats anything. This is only going to be for fun and practice for me.

Thanks for the input.
 

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The 185 are not noticable compared to 230's. i have shot both in the past two weekends and i really cant tell. Maybe after you shoot a match you will notuce but for a trip to the range i cant really tell.
 

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I have not noticed the difference in recoil myself. When I was a .45 pistol owner, I mostly used 230 grain bullets in my M1911 full size pistol, and I shot bowling pins where speed was very important and I needed to keep the recoil down. But switching to lighter bullets didn't really reduce my perception of the recoil, but it did result in the pins not jumping off the table as reliably.
 

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I couldn't tell the difference in recoil either. I did think the Fiocchi 185 HPs were a little more accurate, but that could have been my imigination!
 

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I'm good at asking ridiculous questions, but I'm really curious. I do not reload, so my knowledge of loads is absolutely nil.

What is the difference in the powder load between the two weights. Seems to me that if you go with the 230 gr you'd have to give up powder space. Do you just compensate with a different powder, or what? Just seems that, if you change powder as you increase weight, differences in "kick" are not going to be discernible. Forgive me, but it's a question I've always wanted to ask, and this seems the opportune time. :?
 

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Yes, smaller bullets take more powder. It's not because of case capacity though, its because of pressure. Pushing the heavier bullet through the barrel helps keep pressure up compared to lighter weight projectiles.... therefore; less powder is needed for heavier projectiles to build the proper pressure.

ETA: If you look at a reloading manual, you'll see pretty much across the board, lighter bullets get heavier powder loads compared to the heaviest bullets in the cartridge offerings..... But some cartridges are very versatile like the .30-06. If you look at the reloading manual, for the lightweight range of bullets, you'll find powders listed that build good pressure with lighter weight bullets... but then look at the heavy weight bullet range, and all the powders have changed due to the higher pressures of the heavier bullet and the powders listed will keep the pressure down.
 

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Interesting....A friend of mine told me that heavier weight bullets would have lower felt-recoil. He said 180gr. bullets have less felt-recoil than 155gr. ones. (for .40 S&W) I told him .40 S&W will snap no matter what. :shattered:

I can tell the difference between my full-size 1911 -vs- commander-size 1911....but not different bullet weights.
 

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I thought the most of you would have said you could feel it.
I can feel the difference. Though it is slight the 230 feels to me like a heavier kick than the 185, not to mention the 230s shoot high in my 1911 so for me and my shooting style and setup I would go 185. You should go to the range with both and compare mags back to back with your setup!
 

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1clearshot said:
Interesting....A friend of mine told me that heavier weight bullets would have lower felt-recoil. He said 180gr. bullets have less felt-recoil than 155gr. ones. (for .40 S&W) I told him .40 S&W will snap no matter what. :shattered:

I can tell the difference between my full-size 1911 -vs- commander-size 1911....but not different bullet weights.
The seat of my pants tells me Chevron gasoline makes my car faster. Does it make it true? Maybe, maybe not. Only a dyno can tell.

The recoil pulse may be different, but overall, I'm betting the "felt recoil" energy is approximately the same. The difference being perceived may only be the amount of rearward energy vs muzzle flip energy.
 

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JiG said:
1clearshot said:
Interesting....A friend of mine told me that heavier weight bullets would have lower felt-recoil. He said 180gr. bullets have less felt-recoil than 155gr. ones. (for .40 S&W) I told him .40 S&W will snap no matter what. :shattered:

I can tell the difference between my full-size 1911 -vs- commander-size 1911....but not different bullet weights.
The seat of my pants tells me Chevron gasoline makes my car faster. Does it make it true? Maybe, maybe not. Only a dyno can tell.

The recoil pulse may be different, but overall, I'm betting the "felt recoil" energy is approximately the same. The difference being perceived may only be the amount of rearward energy vs muzzle flip energy.
Great post
 

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While my 185 grain plus P are hollow points,and used in my 4-inch barrel ZD45, while my 230 grain are used when I had a 5-inch Kimber 1911. The idea of using a lighter and hotter round to stabilize it due to the shorter barrel.

As to recoil, to me the fell the same when used in the length of barrel they were intended for.
 

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Free Recoil Energy:

Using this formula, you can calculate the amount of recoil for any given gun and load:

Free Recoil Energy (ft-lbs) = (W1 Vp + 4700 W2)squared / 64.348 Wg

W1 = weight of bullet in pounds
W2 = weight of powder charge in pounds
Wg = weight of gun in pounds
Vp = muzzle velocity of bullet in fps.
7000 grains in one pound

OK, let's do some math... I will be using the Lyman reloading manual for .45 acp and using max loads for 185 grain and 230 grain bullets using two different powders that are supposed to produce the same C.U.P. (pressure)

185 grain loads: Bullseye Powder = 5.6 grains... Velocity 975 fps. 16,600 C.U.P.

W1 = 185/7000= .026
W2 = 5.6/7000 = .0008
Wg = 2.44 (approx 1911 weight w/o magazine)
Vp = 975

(.026 x 975 + 4700 x .0008)squared / 64.348 x 2.44
(25.35 + 3.76)squared / 157.009
(29.11)squared / 157.009
847.392/157.009 = 5.397 ft-lbs of free recoil energy

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230 grain loads: Power Pistol Powder = 7.2 grains... Velocity 858 fps 16,600 C.U.P.

W1 = 230/7000 = .032
W2 = 7.2/7000 = .001
Wg = 2.44 (same pistol weight)
Vp = 858

(.032 x 858 + 4700 x .001)squared / 64.348 x 2.44
(27.456 + 4.7)squared / 157.009
(32.156)squared / 157.009
1034.008 / 157.009 = 6.58 ft-lbs of free recoil energy

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Ok, what did we learn from that exercise? We learned that given the same pressure inside the barrel in the same weight pistol, the bigger bullet will recoil more..... there's that whole "equal and opposite" reaction thing showing up..... but if you are like me, you noticed that 975 fps is a bit slow for a 185 grain load.... let's look at something a little more normal in speed to compare with the relatively normal speed of 858 for the 230 grain.

A quick google search found that Remington standard load 185 grain ammo shoots 1015 fps.... so we'll use a load in the reloading manual that states 1015fps will be the velocity.... Lyman lists Blue Dot powder with 10.2 grains of powder.

W1 = 185/7000 = .026
W2 = 10.2 / 7000 = .0014
Wg = 2.44
Vp = 1015

(.026 x 1015 + 4700 x .0014)sq / 64.348 x 2.44
(26.39 + 6.58)sq / 157.009
(32.97)sq / 157.009
1087.021 / 157.009 = 6.923 ft-lbs of free recoil energy

What a difference 40 fps makes with 185 grain bullets. 975 fps produced only 5.397 ft-lbs of recoil, but sped up 40 fps faster, it had more recoil than the 230 grain load did. Not much more, and I'm betting the difference between the 1015 fps 185 grain load and the 858 fps 230 grain load wouldn't be perceptible to a human.
 

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Discussion Starter · #14 ·
JiG said:
Free Recoil Energy:

Using this formula, you can calculate the amount of recoil for any given gun and load:

Free Recoil Energy (ft-lbs) = (W1 Vp + 4700 W2)squared / 64.348 Wg

W1 = weight of bullet in pounds
W2 = weight of powder charge in pounds
Wg = weight of gun in pounds
Vp = muzzle velocity of bullet in fps.
7000 grains in one pound

OK, let's do some math... I will be using the Lyman reloading manual for .45 acp and using max loads for 185 grain and 230 grain bullets using two different powders that are supposed to produce the same C.U.P. (pressure)

185 grain loads: Bullseye Powder = 5.6 grains... Velocity 975 fps. 16,600 C.U.P.

W1 = 185/7000= .026
W2 = 5.6/7000 = .0008
Wg = 2.44 (approx 1911 weight w/o magazine)
Vp = 975

(.026 x 975 + 4700 x .0008)squared / 64.348 x 2.44
(25.35 + 3.76)squared / 157.009
(29.11)squared / 157.009
847.392/157.009 = 5.397 ft-lbs of free recoil energy

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230 grain loads: Power Pistol Powder = 7.2 grains... Velocity 858 fps 16,600 C.U.P.

W1 = 230/7000 = .032
W2 = 7.2/7000 = .001
Wg = 2.44 (same pistol weight)
Vp = 858

(.032 x 858 + 4700 x .001)squared / 64.348 x 2.44
(27.456 + 4.7)squared / 157.009
(32.156)squared / 157.009
1034.008 / 157.009 = 6.58 ft-lbs of free recoil energy

------------------------

Ok, what did we learn from that exercise? We learned that given the same pressure inside the barrel in the same weight pistol, the bigger bullet will recoil more..... there's that whole "equal and opposite" reaction thing showing up..... but if you are like me, you noticed that 975 fps is a bit slow for a 185 grain load.... let's look at something a little more normal in speed to compare with the relatively normal speed of 858 for the 230 grain.

A quick google search found that Remington standard load 185 grain ammo shoots 1015 fps.... so we'll use a load in the reloading manual that states 1015fps will be the velocity.... Lyman lists Blue Dot powder with 10.2 grains of powder.

W1 = 185/7000 = .026
W2 = 10.2 / 7000 = .0014
Wg = 2.44
Vp = 1015

(.026 x 1015 + 4700 x .0014)sq / 64.348 x 2.44
(26.39 + 6.58)sq / 157.009
(32.97)sq / 157.009
1087.021 / 157.009 = 6.923 ft-lbs of free recoil energy

What a difference 40 fps makes with 185 grain bullets. 975 fps produced only 5.397 ft-lbs of recoil, but sped up 40 fps faster, it had more recoil than the 230 grain load did. Not much more, and I'm betting the difference between the 1015 fps 185 grain load and the 858 fps 230 grain load wouldn't be perceptible to a human.
I feel way smarter now. You lost me on the math tho. I couldn't tell what your order of operations were. Where's The Math Teacher?
Thanks everyone for the help. I never would have figured this for the outcome. Glad I asked. :D
 

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1clearshot said:
Thanks JiG, for the mathematical proof....

You NEED to get out more....

I'm serious. :)
I do, seriously....

Saturday, I was in Gainesville, then to Athens, back to Cornelia, then to Conyers, then finally back home for the evening.

Today, I had to go to Gainesville again and then to Spartanburg, SC. Just got back a little bit ago.

I love my job. I never know what my day will bring me, what paths I will take, and the places and people I'll see and meet. But all that driving does afford me some time to contemplate "stuff".

As far as that post was concerned, that was me just using a reloading manual. The formula is in the back of the book. All you have to do is find and input the data and put it to practical use. Anybody who took basic algebra should be able to do it.
 

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JiG is the smartest gun/reloading/bullet/rifle/pistol/primer/ammo/case/milsurp ammo/firearm guy i know...........
just sayin'
 
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