147 grain significantly less recoil than 115? - XDTalk Forums - Your HS2000/SA-XD Information Source!

Menel · 03-01-2008, 04:21 PM

I am a bit new to shooting. When I got my gun, I shot one full mag of my Rangers, I justified it saying to myself I wanted to be sure it cycled well, even though everyone on here says it does, so it was just for the hell of it.

Since then I've only shot WWB 115, walmart value packs.

Rangers RA9T's are 147gr.

Today, I took the top 4 bullets off the top out of my carry mag that I have been cycling between. Mixed them up as every 3rd shot with my WWB just to see how it goes.

They were noticeable lighter. The noise and recoil was signifcantly less on the Rangers...!?... I expected more... It was almost like those shots were .22's or something very light. It was kind of nice actually.

I found a online recoil calcuator. Used generic wiki velocity for the 115gr, found an FBI database test for velocity on the Rangers. Used my reloaders reference for the generic gunpowder amount for generic lead 115gr and 147 grain.

Calculation turned out saying the 147 should have a bit more recoil... puzzled. Is this normal?

propellerhead · 03-01-2008, 04:42 PM

I would think it would be more too. Read up more on those 147s. I seem to recall reading something about them being too heavy that you lose velocity.

**bruce21b** · 03-01-2008, 05:15 PM

Hi,

ive been shooting WWB 115 grain FMJ and 147 grain JHP's and FMJ for as long as i can remember....

the "premium" loads i carry in 147 grain (federal hst's) i notice have a very slightly bit more recoil than the 115 grain......but after shooting both of them for so long, i cant really tell any difference..

keep in mind that the WWB are more or less a "generic" brand of ammo, and winchester uses a lower grade powder for them...where the "premium" stuff uses powder with a little more "bite" to it....

mcb · 03-01-2008, 06:44 PM

Recoil is a nasty little problem to really nail down well. First you have the calculated recoil impulse, the recoil impulse an engineer would calculate is a change in momentum. But this is a simple equation that does not describe the details of the recoil just the total impulse. Frequently this number when comparing loads does not jive with the felt recoil since felt recoil is more than just the total change in momentum but also includes the shape of that momentum impulse and other factors like the weight of the weapon, type of action, and the amount of muzzle blast.

The engineering part is easy. Total recoil impulse is a change of momentum. If a bullet with mass "M" leaves the barrel at velocity "V" that equates to a momentum "P" change (from rest) of P=MxV. Although that tells you the magnitude of the recoil it does not really fully describe the recoil impulse.

A light bullet, say your 115gr WWB leaving the muzzle at 1190fps would have a recoil of 0.608 slug-ft/sec. Units are not important you can ignore them. (If your curious 4.44x10^-6 slugs per grain. Slugs the English unit of mass, grains being a measure of weight)

Now if we loaded a 147gr 9mm bullet to have the same total recoil impulse of the 115 gr load of 0.608slug-ft/sec we would have a 147gr bullet going about 930fps. This would give us the same total recoil impulse as calculated above. But I guarantee, as the OP has already observed, that it feels different than the light load, despite that they would have exactly the same total recoil impulse.

Why do they feel different? That's because the way they get to that total momentum change is different and the shooter can feel that difference. Assuming we are shooting the two loads in the same gun. Light bullets have to accelerate very quickly down the barrel to achieve their higher muzzle velocity and thus experience higher accelerations over a shorter period of time. Heavier bullets that have the same total recoil impulse are going slower so they see lower acceleration over a longer span of time. The span of time here is very short, maybe 0.5-0.6ms for the 115gr and 0.6-0.7ms for the 147gr but it makes a difference. Both of these situation can result in the same total recoil impulse but the light bullet load will feel sharp and snappy were the heavy bullet load will feel slow and pushy. Most shooter find pushy loads are more comfortable on the hands.

If you talk to many shooter that are shooting a lot of USPSA and/or IDPA competition you will find that most shooters are shooting the heaviest bullet commonly used in their chosen caliber. 9mm - 147gr, 40S&W 180&200gr, 45cal - 230gr. Given that the competition specifies the minimum amount of recoil (Power Factor is just another name for total recoil impulse using different units) the best you can do is use heavy bullets to get to the power factor thus making it more pushy and less snappy.

A second factor the often comes to play here is muzzle blast. Light bullets, especial cheap factory ammunition, use really fast burning powders. Fast powders are cheap but results in relative high pressures still in the barrel as the bullet exits. This results in much louder muzzle blast. Heavier bullet require the use of slower burning powders this often results in slightly lower pressures as the bullet exits the barrel. This is often true but not always. You can sometime find light bullet loads with moderate muzzle blast and conversely heavy loads that are quite noisy. None the less a lower muzzle blast help the perception of less recoil. Just doubling up on your hearing protection helps a lot. Try plugs and muffs at the range some time.

Rambling but hopefully helpful
mcb

Menel · 03-01-2008, 06:55 PM

Thank you! it makes since especially the points on acceleration.

The Knight Of Light · 03-01-2008, 07:28 PM

What MCB said....

jimmyjam101 · 03-01-2008, 08:24 PM

Quote:

Originally Posted by bruce21b

Hi,

ive been shooting WWB 115 grain FMJ and 147 grain JHP's and FMJ for as long as i can remember....

the "premium" loads i carry in 147 grain (federal hst's) i notice have a very slightly bit more recoil than the 115 grain......but after shooting both of them for so long, i cant really tell any difference..

keep in mind that the WWB are more or less a "generic" brand of ammo, and winchester uses a lower grade powder for them...where the "premium" stuff uses powder with a little more "bite" to it....

I don't think this is accurate, because I personally spoke with a winchester ammo representative, and they told me the only difference between wwb and winchester premium ammo is the color of the box. I was actually asking about wwb defense ammo of the same bullet weight in rangers.
Maybe they mis informed me, but I doubt it.

**Loves2Shoot** · 03-01-2008, 08:31 PM

Quote:

Originally Posted by jimmyjam101

I don't think this is accurate, because I personally spoke with a winchester ammo representative, and they told me the only difference between wwb and winchester premium ammo is the color of the box. I was actually asking about wwb defense ammo of the same bullet weight in rangers.
Maybe they mis informed me, but I doubt it.

That is scary, because WWB qc is crap.

The Knight Of Light · 03-01-2008, 08:36 PM

Quote:

Originally Posted by Loves2Shoot

That is scary, because WWB qc is crap.

Very Scary.

03-01-2008, 04:21 PM	#1
Menel XDTalk Member Join Date: Jan 2008 Location: Atlanta, GA Posts: 68	147 grain significantly less recoil than 115? I am a bit new to shooting. When I got my gun, I shot one full mag of my Rangers, I justified it saying to myself I wanted to be sure it cycled well, even though everyone on here says it does, so it was just for the hell of it. Since then I've only shot WWB 115, walmart value packs. Rangers RA9T's are 147gr. Today, I took the top 4 bullets off the top out of my carry mag that I have been cycling between. Mixed them up as every 3rd shot with my WWB just to see how it goes. They were noticeable lighter. The noise and recoil was signifcantly less on the Rangers...!?... I expected more... It was almost like those shots were .22's or something very light. It was kind of nice actually. I found a online recoil calcuator. Used generic wiki velocity for the 115gr, found an FBI database test for velocity on the Rangers. Used my reloaders reference for the generic gunpowder amount for generic lead 115gr and 147 grain. Calculation turned out saying the 147 should have a bit more recoil... puzzled. Is this normal?

03-01-2008, 04:42 PM	#2
propellerhead XDTalk 3K Member Join Date: Apr 2006 Location: Foat Wurth, TX Posts: 3,477	I would think it would be more too. Read up more on those 147s. I seem to recall reading something about them being too heavy that you lose velocity. __________________ XD-9 Tactical for practice & IDPA, XD-40 Subcompact for concealed carry, XD-45 Service for home defense. Three purposes, three calibers, three models. One gun.

03-01-2008, 05:15 PM	#3
bruce21b XDTalk 100 Member Join Date: Jan 2008 Posts: 447	Hi, ive been shooting WWB 115 grain FMJ and 147 grain JHP's and FMJ for as long as i can remember.... the "premium" loads i carry in 147 grain (federal hst's) i notice have a very slightly bit more recoil than the 115 grain......but after shooting both of them for so long, i cant really tell any difference.. keep in mind that the WWB are more or less a "generic" brand of ammo, and winchester uses a lower grade powder for them...where the "premium" stuff uses powder with a little more "bite" to it.... __________________ Springfield XD-9 Service Sig Sauer P-229 Wilson Combat CQB (when gas prices come down to earth)

03-01-2008, 06:44 PM	#4
mcb XDTalk 2K Member Join Date: Feb 2005 Location: North East Ohio Posts: 2,038	Recoil is a nasty little problem to really nail down well. First you have the calculated recoil impulse, the recoil impulse an engineer would calculate is a change in momentum. But this is a simple equation that does not describe the details of the recoil just the total impulse. Frequently this number when comparing loads does not jive with the felt recoil since felt recoil is more than just the total change in momentum but also includes the shape of that momentum impulse and other factors like the weight of the weapon, type of action, and the amount of muzzle blast. The engineering part is easy. Total recoil impulse is a change of momentum. If a bullet with mass "M" leaves the barrel at velocity "V" that equates to a momentum "P" change (from rest) of P=MxV. Although that tells you the magnitude of the recoil it does not really fully describe the recoil impulse. A light bullet, say your 115gr WWB leaving the muzzle at 1190fps would have a recoil of 0.608 slug-ft/sec. Units are not important you can ignore them. (If your curious 4.44x10^-6 slugs per grain. Slugs the English unit of mass, grains being a measure of weight) Now if we loaded a 147gr 9mm bullet to have the same total recoil impulse of the 115 gr load of 0.608slug-ft/sec we would have a 147gr bullet going about 930fps. This would give us the same total recoil impulse as calculated above. But I guarantee, as the OP has already observed, that it feels different than the light load, despite that they would have exactly the same total recoil impulse. Why do they feel different? That's because the way they get to that total momentum change is different and the shooter can feel that difference. Assuming we are shooting the two loads in the same gun. Light bullets have to accelerate very quickly down the barrel to achieve their higher muzzle velocity and thus experience higher accelerations over a shorter period of time. Heavier bullets that have the same total recoil impulse are going slower so they see lower acceleration over a longer span of time. The span of time here is very short, maybe 0.5-0.6ms for the 115gr and 0.6-0.7ms for the 147gr but it makes a difference. Both of these situation can result in the same total recoil impulse but the light bullet load will feel sharp and snappy were the heavy bullet load will feel slow and pushy. Most shooter find pushy loads are more comfortable on the hands. If you talk to many shooter that are shooting a lot of USPSA and/or IDPA competition you will find that most shooters are shooting the heaviest bullet commonly used in their chosen caliber. 9mm - 147gr, 40S&W 180&200gr, 45cal - 230gr. Given that the competition specifies the minimum amount of recoil (Power Factor is just another name for total recoil impulse using different units) the best you can do is use heavy bullets to get to the power factor thus making it more pushy and less snappy. A second factor the often comes to play here is muzzle blast. Light bullets, especial cheap factory ammunition, use really fast burning powders. Fast powders are cheap but results in relative high pressures still in the barrel as the bullet exits. This results in much louder muzzle blast. Heavier bullet require the use of slower burning powders this often results in slightly lower pressures as the bullet exits the barrel. This is often true but not always. You can sometime find light bullet loads with moderate muzzle blast and conversely heavy loads that are quite noisy. None the less a lower muzzle blast help the perception of less recoil. Just doubling up on your hearing protection helps a lot. Try plugs and muffs at the range some time. Rambling but hopefully helpful mcb __________________ If at first you don't succeed; RELOAD _ _ _ _ My web site

03-01-2008, 07:28 PM	#6
The Knight Of Light XDTalk 5K Member Join Date: May 2005 Location: Omaha, Nebraska Posts: 8,708 Blog Entries: 12	What MCB said.... __________________ No Matter Where You Go, There You Are. USPSA #L3077 What a great number!!! http://theknightoflight.blogspot.com/ Creator of TOP 'O' THE PAGE!!! Moose Fight

03-01-2008, 06:55 PM	#5
Menel XDTalk Member Join Date: Jan 2008 Location: Atlanta, GA Posts: 68	Thank you! it makes since especially the points on acceleration.

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