Full-length barrel porting?

[Hostile Amish]

I had an idea to do top barrel porting for the full length of the barrel, giving about 2-3 in for the chamber space. I want to drill 5mm holes about 1in apart for the full length of the barrel, to reduce recoil. Would this affect accuracy or any other function of my rifle? The gun in question is a rifle, so ability to recycle the bolt is not an issue.

 

[rbernie]

Recoil reduction is best accomplished at the end of the barrel for several reasons; to preserve pressure in the barrel for as long as possible (otherwise you'll get very little velocity), and because of leverage effects diminishing as you move closer and closer to the chamber.

Drilling holes up to 3" from a rifle chamber would be a very bad idea.

 

[rcmodel]

VERY BAD idea!

Chamber pressure there is at almost maximum and blast would be horrific!

As rbernie noted, all the leverage is at the muzzle, and ports close to the center of the rifle would have little noticeable effect, other then blowing your hair off from the tremendous blast/shock wave.

rc

 

[nitetrane98]

Just doing a little ciphering, with 20 5mm holes you'd have a combined area removed of roughly .608". Or the equivalent of 1 1/2 more muzzles in a .30 caliber rifle. I can't see that not hurting velocity very badly. I can almost envision the bullet going plop in the dirt in front of the barrel. Ok maybe not that bad.

 

[rcmodel]

It would be way more then 1 1/2" of barrel length.

All that pressure lost that close to the chamber would have a profound effect on velocity.

rc

 

[krs]

And to think that there's people out there dreaming up such ideas who go ahead and do it without even asking anyone whether it'd be a workable plan.

At least the OP asked.

 

[nitetrane98]

I was talking about area, not length, but still was wrong. Yeah, you're sure right. Area of a .30 diameter circle is .071sq ". Area of 20 5MM holes is .600sq". How about nearly 8 1/2 muzzle diameters worth of holes.

 

[rcmodel]

Another factor I just thought of is, you don't want ports that you can reach with the support hand on a rifle.

The blast will cut your fingers right off if you happen to fire a shot with one over a port.

rc

 

[JackOfAllTradesMasterAtNone]

Curiosity is going to kill this cat some day..

But I've got to ask. What rifle are you trying to reduce recoil on?

And Rcmodel is correct. The pressures are still quite high, (at least 90%), a couple inches into the barrel. I'll bet that half of the effective muzzle blast would be released just forward of the chamber. Do ya think that muzzle compensated barrels are loud..? With a .30cal something or other, this would give you a new meaning of loud at the cost of losing some bullet velocity. -And recoil would not be reduced much. Newtons law still applies. Porting a rifle barrel that far back, (not knowing the cartridge/caliber used..), could also weaken the barrel.

RC talking about forward hand placement... I visualized some guy looking at his mom and buddies as they bask in the sun on puffed up semi tire inner tubes in an above ground pool with a Chevy tailgate as the diving board... "Hey ma, watch this."
Boom! -Parts of fingers fly skyward. At least two of those fingers land in the pool and the resident Oscar gobbles them up. The Pitbull in the back yard gets one other finger as a doggy treat, and the other lands in the tornado damaged rain gutter of the mobile home -never to be found.

If you can't handle the recoil. Shoot a rimfire rifle then build up to that 'big gun'. You might just want to install a quality recoil pad like the Decelerator.

How about nearly 8 1/2 muzzle diameters worth of holes.

Ah true.. But taking ~2 2/3" off the end of the barrel isn't the same as putting those holes so close to the chamber end of the barrel.

there's people out there dreaming up such ideas who go ahead and do it without even asking

KRS.. SO so True!

-Steve

 

[rcmodel]

You know, I have a Marlin 94 .44 Mag Guide-Gun with a 16 1/4" ported barrel.

Right after I got it, I was shooting out the truck window at a 100 yard steel gong.
In order to get past the trucks side mirror, I slid my left hand way out front on the barrel, put a support finger on the mirror to keep the muzzle away from it, and squeezed one off.

I had my thumb laying right next to a port, and it took all the skin off down to the meat.

And I was shooting light .44 Specials in it!

rc