Do Ported Chokes Reduce Recoil?


The below was generated in response to a discussion on ported chokes.


I will probably be dodging bricks that are thrown in response to this.

The below answer is my opinion based on my knowledge and belief.

Does porting reduce recoil in shotguns??

If so, how does it work?

Recoil of any shotgun is based on 3 primary factors and 1 secondary factor.

Primary factors are

1-Weight of the gun

2-Projectile weight (combined weight of shot charge and wad)

3-Speed of the projectile

Recoil can be reduced or increased by a noticeable amount by changing anyone of the above factors. Increase the weight of the gun, reduce the projectile weight or reduce the velocity of the projectile by any significant amount and you will reduce the recoil by a significant amount. 

Secondary factor

1-Muzzle pressure

Several years ago I talked with the folks at the H.P. White lab and inquired if anyone had conducted tests to determine what the muzzle pressure of shotguns were. They told me they had not nor did they know of anyone who had.

They did tell me that they thought that the same formula that they use for centerfire rifle cartridges would hold true for shotshells, (5 to 1) that is a rifle cartridge that developed max chamber pressure of 50000 CUP would have approx 10000 CUP at the muzzle. If we apply this to a shotshell load of 12000 LUP we would have approx 2400 LUP at the muzzle. This is a very substantial reduction in pressure.

The residual gas that escapes into the atmosphere after the shot charge leaves the barrel functions as a very crude rocket engine with an incredibly short fuel burn time. This gas escaping at high speed adds to the recoil generated from pushing the projectile weight up to its ultimate velocity. However, in my opinion because of the very low pressure at the muzzle the effect on the amount of recoil generated is a small amount.

Porting the choke tube will bleed off some of the escaping gas at right angles thus reducing the “rocket engine effect” thereby reducing recoil by a very small amount. Please understand that I have not measured the effects of this on a scientific basis.

George Trulock

Trulock Chokes
229-762-4678  work
229-762-4050  fax                                                 

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5 Responses to Do Ported Chokes Reduce Recoil?

  1. russell hansen says:

    i just bought a new cz mod. 912 12gage. i was told it had a very soft recoil. Boy were there wrong. it kicks like a mule. I want tobye a extended choke that is ported for duck hunting. The shotgun is made bye Huglu arms. Doyou know witch one i would use. Thank you for your time

    • admin says:

      Ported chokes do reduce recoil by a small amount. To the best of my knowledge all CZ shotguns use the Mobil style choke tube. As you do not tell me whether you are shooting over decoys or pass shooting I am having to make a suggestion based on what I think would work well for you. I would suggest a PHBER12710P. I am assuming steel shot in the 2 to 4 size range.
      George Trulock

  2. bubbleshooter says:

    Hi, how’s it going? I hope you do well. I needed to say that I like Do Ported Chokes Reduce Recoil? | Trulock Chokes.

  3. Joseph Yachouy says:

    Dear Trulock Team

    DO you have pattern result for Beretta Cal 20 at 40 Yrds ?

    For Factory Modified Chocke and for Trulock Precision hunter Modified Choke ?

    Thank you in advance

    • admin says:

      Sorry, but I don’t have photo’s of that specific pattern to compare with our PH choke patterns.
      George Trulock