Pressure vs recoil question

[gerry]

I'm curious between 2 similar loads in a 270 WSM and 7mm Rem mag, same powder charge with the same weight bullets the only difference is the 270 WSM load is at +/- 63,000 psi and the 7mm Rem Mag is at +/- 59,000 psi.

Would there be any noticeable difference in recoil between the two rounds? I was surprised at how similar the loads are in Hogdon's website they only difference is the the 270 WSM is loaded to a higher pressure. Trying to decide what to do with my Sako rifle, I have a spare Sako 7mm Rem mag barrel sitting here and with a powder like IMR 4451 or H 4350 it could make a good gun for my wife to use on heavier game with a good 139-150 gr bullet. I also have thought about selling it and getting her a second Tikka T 3 in 270 WSM and load the same powders with the same weight bullets.

Decided to use the Rem 700 for the 308 Norma project, need to figure out what to do with the Sako.

 

[Ridgerunner665]

Recoil is a product of the mass that is being ejected (powder and bullet).... The velocity matters in regards to recoil, and pressure matters in regards to velocity.... But pressure doesn't directly effect recoil.

 

[truck driver]

Gerry I'd get the 7mm MSM reamer from Scotty and have the Sako rechambered. With the results he has been getting along with Lesili I wouldn't hesitate if I had a 7mm rem mag.

 

[SJB358]

Gerry I'd get the 7mm MSM reamer from Scotty and have the Sako rechambered. With the results he has been getting along with Lesili I wouldn't hesitate if I had a 7mm rem mag.

I can't argue with that only I don't own the reamer. It is a good idea cause even the fireform loads with 4350 and 140's are really capable for most anything we all hunt. Then you have the option of going up from there.

You mentioned recoil between the 7RM and 270 WSM. I'm not sure I'm accurate enough as a sensor but even running 150's at 3150 from my 270WSM doesn't feel like it bumps me as hard as the 7. Similar stocks between the two of them as well but honestly they feel about the same Gerry. I'd think any real difference is the stock itself.

Having a good barrel around is reason enough to stick with a 7.... But you might as well make it all it can be. Kinda like surgery, since you'll already have it opened up you might as well fix it up while your there. :mrgreen:

 

[DrMike]

For all practical purposes, if the bullet mass and powder charge are identical, recoil will be equivalent. This does assume that stock design distributes felt recoil similarly. RR gave a good summation, Gerry.

 

[bbearhntr]

Does each rifle weigh the exact same? That may have more of an effect on felt recoil.

 

[Woodburner]

Heavier the rifle less felt recoil, I think Newton's Laws come into play. Action and reaction always equal and opposite.

 

[jimbires]

you can run the loads through quickload and get the recoil . this is how I figure recoil when I'm helping out a new shooter .

 

[gerry]

If you run the loads through JM Ballistics they would come out exactly the same. The reason I asked the question was in my younger years when I ran a few hotter loads in my 308 Norma and 35 Whelen recoil was noticeably heavier. Could have just been the extra speed but I did wonder at the time if it could also have been the higher pressure. Thanks for your thoughts guys.

 

[muleman]

Gerry,
Felt recoil can vary quite a bit between two rifle with the same load. Weight of the rifle and stock design can greatly effect felt recoil. I have a 300RUM that 'll give me a headache in less than 20 rounds. My brothers 340Bee is much easier to handle because the stock design pushes the gun up instead of straight back. Their recoil energy is very similar.

Scott

 

[truck driver]

I'm not a ballistics engineer but I do know that for some reason the 225gr .358 bullets seem to have heavier felt recoil in my rifle as compared to a 250gr and I think the bullet design has a lot to do with it also.

 

[Gunner46]

Some of the 'felt' or 'perceived' recoil has more to do with the recoil impulse speed, than the recoil energy. Think of it as a fast slap vs a slow punch. While both may have the same amount of energy, the faster one may sting a bit more.

 

[Oldtrader3]

Chamber pressure has two resultant recoils: the thrust of the chamber pressure times the area of the brass case base. Plus two types of ejecta: the bullet weight at muzzle velocity and the ejecta weight and jet effect (gas and unburned powder) at Mach 3.