ported or not?

[mogwai]

I have a Mossberg 24" barrel for my 12 ga 870.  It is ported, and shoots quite well with its favorite slug.  However I wish the barrel was shorter...most of my guns sport 20-22" barrels. 

I am considering having the barrel shortened to 20" to improve handling.  This would remove the porting.  Will this MATERIALLY increase recoil?

[deerhunter10]

Mogwai according to the info I received over the past year from gunsmiths and gun manufactures, pressures in shot guns are much lower than those in rifles. Therefore recoil is only about 10-15% verse's 40-50% in a rifle. The main thing it does is prevent muzzle rise. Tar-Hunt put them on their guns for that purpose along with the fact that it helped their sabots separate sooner.

I'd look into how short you want to go. They say 23 inches seems to be the optimum barrel length for powder burn and slug stabilization. However there is some controversy on how long it actually takes the powder to completely burn in a shot gun barrel. Remington told me it's done in 15-18 inches, and some gunsmiths have said 20-23 inches. So you may want to do a little research before you wack that thing down to far.

[nkhunter]

I have friends with the ported mossberg bolt actions. They claim the porting doesn't help all that much. I notice that mossberg has a barrel program where you can send in your unported barrel to have ported.

[mogwai]

Thanks guys.   I'll talk it over with my gunsmith before making a final decision, but I'm leaning toward 20-21".  That's the same as my 20 ga bird gun and my open-sighted 12 ga slug barrel