Recoil & Bullet Weight

Triple BB

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I'm shooting a 338 Edge with a 300 grn Berger. I also shoot a 300 RUM. Both rifles are similar in build and weight including having the same brakes. I'm shooting 199 grn Hammer Hunters in the RUM. The difference in recoil is night and day between the two.

My question is, how much bullet weight would I have to drop to start noticing a reduction in recoil with the Edge?
 

BallisticsGuy

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How much to "notice" can't say. Everyone handles recoil differently. You could be a 500lbs 4'9" tall butterball of a man (spherical but quite pointy in places) or you might have a physique more like mine and every other average guy, 5'10" @ 170lbs and strong but not overtly muscular or anywhere in between. Your rifle could be a fixed emplacement weighing many hundreds of pounds or it could be a 6lbs maker of recoil formed human tacos. When shooting something like a 10lbs tactical .308win I will EASILY notice the difference between a 110gr and a 150gr and a 150gr from a 180gr. I cannot really tell a 168gr from a 150 and I can only just discern it from a 180.

When shooting a suppressed .338wm I can't tell the difference between a 250gr and a 225gr but a 200gr and a 250gr are notably different to each other.

So, I'll say when looking at power levels that are up in high power rifle territory, 50gr of bullet weight is really quickly noticeable. Noticing so much that you start praising the Flying Spaghetti Monster for reaching down with his noodly appendage and taking the pain away, that's going to come down to the ratio of heavy bullet recoil to light bullet recoil and what recoil velocity is produced. Recoil Velocity matters more than recoil energy here... You can take a million pounds of recoil if you do it over a long enough time. The shorter the time the more violent the sensation.

So let's calculate recoil velocity: Add up the total weight of the powder and bullet. Divide that by the weight of the rifle. Multiply the result of that by the velocity to get recoil velocity. Compare the recoil velocity of one against the other. Now you know how fast your rifle will slap your shoulder and that should be a decent idea of how much it'll hurt compared to a different load in the same rifle.
 

Triple BB

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How much to "notice" can't say. Everyone handles recoil differently. You could be a 500lbs 4'9" tall butterball of a man (spherical but quite pointy in places) or you might have a physique more like mine and every other average guy, 5'10" @ 170lbs and strong but not overtly muscular or anywhere in between. Your rifle could be a fixed emplacement weighing many hundreds of pounds or it could be a 6lbs maker of recoil formed human tacos. When shooting something like a 10lbs tactical .308win I will EASILY notice the difference between a 110gr and a 150gr and a 150gr from a 180gr. I cannot really tell a 168gr from a 150 and I can only just discern it from a 180.

When shooting a suppressed .338wm I can't tell the difference between a 250gr and a 225gr but a 200gr and a 250gr are notably different to each other.

So, I'll say when looking at power levels that are up in high power rifle territory, 50gr of bullet weight is really quickly noticeable. Noticing so much that you start praising the Flying Spaghetti Monster for reaching down with his noodly appendage and taking the pain away, that's going to come down to the ratio of heavy bullet recoil to light bullet recoil and what recoil velocity is produced. Recoil Velocity matters more than recoil energy here... You can take a million pounds of recoil if you do it over a long enough time. The shorter the time the more violent the sensation.

So let's calculate recoil velocity: Add up the total weight of the powder and bullet. Divide that by the weight of the rifle. Multiply the result of that by the velocity to get recoil velocity. Compare the recoil velocity of one against the other. Now you know how fast your rifle will slap your shoulder and that should be a decent idea of how much it'll hurt compared to a different load in the same rifle.
Definitely the kind of info I’m looking for. Thanks...
 

Bravo 4

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You should definitely notice recoil reduction stepping down to 250 grain bullets in your .338 Edge. There is also a difference in perceived recoil between the two cartridges. When I had my .338 Edge a buddy had a very similar rifle (weight and stock) in .300 RUM. The .338 felt more like a shove, the .300 seemed sharper. If you look at the ft-lbs of recoil between the two then the .338 should feel worse, but I enjoyed shooting my .338 more. Today I have a .338 RUM and .300 RUM barrel for the same action, the .300 is a factory spotter and the .338 is slightly heavier with a good brake. The .338 is way more manageable with 300 grain bullets, compared to the .300 shooting 180s. But then again the .338 has a good brake on it.😁
 

Wolf76

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In my edge, I dropped down to the 262 gr hammer from the 300 berger/accubond. It was noticeable. Depending on your application, I'd consider an even lighter hammer.
The 262 (listed as 260 grs on the website) are running 3K fps with n570 out of a 26" barrel. If you say for example that 500 yards is as far as you'd take a kill shot, then run the ballistics on the lighter bullets. You'll see your actually better off in many categories. The heavier bullets don't start making a meaningful difference until 700+ yards.
 

.222 ND

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I used to shoot a 338 rum with 180’s back before dialing became popular. I had those nosler ballistic tips going somewhere just under 3600 fps and recoil wasn’t a problem. Then the heavy bullet dial it up deal came into fashion. I mounted a leupold mark 4 and loaded up some 250 grain matchkings. I headed for the pasture and was going to sight in my new load. I set up a target and drove back aways to touch one off and see how close my bore sighting job was. I stuck the gun out the window and rested it on the mirror. My cousin who had never shot a centerfire rifle before, was sitting in the passenger seat and looked like he had just seen an alien when I turned and asked him if he wanted to try shooting it. We both laughed and swore the two drivers side tires came off the ground when I shot the rifle. He asked if all deer rifles kicked like that and I said not hardly. I was shooting a standard bdl with a light stock and no break. Without a doubt, weight makes a huge difference on foot pounds of recoil.
 

Varmint Hunter

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Projectile weight makes a difference but it's not always as big a difference as you might expect. I tried incrementally dropping the projectile weight of my 30Nosler loads but (naturally) kept increasing the bullet velocity. I was surprised at how little recoil reduction was detectable. The rifle does not have a brake on it. I HATE brakes on my hunting rifles.
 
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P7M13

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There's the physics of recoil, and then there's perception. Geometry of the rifle/stock combination can make a world of difference in perceived recoil.
+/- 3/4" difference in LOP from your ideal fit can turn a rifle into something downright painful to shoot.
I learned that from a 270 (painful) vs. a 7 Rem Mag (shoot 2 boxes, NP). Now I only own rifles that "fit" me.
 

ButterBean

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I'm shooting a 338 Edge with a 300 grn Berger. I also shoot a 300 RUM. Both rifles are similar in build and weight including having the same brakes. I'm shooting 199 grn Hammer Hunters in the RUM. The difference in recoil is night and day between the two.

My question is, how much bullet weight would I have to drop to start noticing a reduction in recoil with the Edge?
It matters a bunch, we are shooting the 101's and 124 Hammers out of the 300RUM and it still kicks but nothing like the 180's
 

Hugnot

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Here is the math formula:


Factors like rifle weight, bullet weight, powder charge weight, & velocity affect recoil. The end result being F.R.E. = 1/2MV**2. The 32.17 is the acceleration in feet per second per second of a falling object. This is divided into the weight of the rifle to get M, the physics guys refer to this value as "slugs". I am at a total loss of how this calculation runs out with a brake screwed onto a muzzle and the same load fired thru the barrel.
Need to know.
 

asd9055

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Here is the math formula:


Factors like rifle weight, bullet weight, powder charge weight, & velocity affect recoil. The end result being F.R.E. = 1/2MV**2. The 32.17 is the acceleration in feet per second per second of a falling object. This is divided into the weight of the rifle to get M, the physics guys refer to this value as "slugs". I am at a total loss of how this calculation runs out with a brake screwed onto a muzzle and the same load fired thru the barrel.
Need to know.
Thats great Hugnot, I just didnt want to confuse him with formulas, that is why I post the calculator site. Just enter numbers, hit caclulate...
Can try same rifle, changing just one parameter like muzzle velocity to see the effects
 

Hugnot

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Good stuff for a spread sheet. Running this stuff for a rifle with a brake would make for reduction of the Wpg value (weight of propellant gases).

I will make a spread sheet to figure out recoil energy.

My smallest rifle is a .20P & the biggest one is a .375-.338. The .375 really kicks hard with 67-68 gr. of H4350 & a 300 Si GK, slightly less felt recoil with a 270 gr, BT (Speer) & 73 gr, H4350 at 2700 fps. The .20 P has so little recoil hits can be spotted thru the scope - ideal for shooting rodents. I have one brake & it is on my 5.56 AR and reduces the recoil enough to spot hits for fast 2nd & 3rd shots. I think it does this by reducing the Wpg value that is the weight of propellant gases, instead of being expelled out the brake traps the gas & diverts it.
 
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