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Pistolgripshotty
September 22, 2012, 08:04 AM
Does anyone have any experience with porting a barrel...I was considering porting mine on my 500 but need a little more knowledge about it. Any info is good info. Thanks!

jaguarxk120
September 22, 2012, 10:20 AM
Some people say it's good and some say it does nothing. I lean to the nothing people.

Shotguns operate at much lower pressures(12,000psi) than a rifle(50,000psi), and venting off some of the powder gas won't do much help in controling recoil.

In rifles part of the recoil impulse is from the jet/rocket effect from the gas comming from the muzzle, and a brake will help control recoil. Shotguns the recoil impulse is more form the fact you are shooting a 492 grain hunk of lead out the barrel.

The porting makes the gun sound louder (venting gas closer to shooter) and some think the ports/holes look cool.

big al hunter
September 22, 2012, 10:46 AM
My 835 came factory ported. It helps with muzzle rise on 3 1/2"mag loads with 1 1/4 oz loads of steel shot or 1 3/8 oz lead turkey loads. It does not seem very effective on 2 3/4" shells. At least I don't notice any difference with other shotguns. If your not hunting turkey it probably wont change much. The best recoil reducer I have found is a flex tech stock. Beneli and Thompson Center have them as an option from the factory. Cuts recoil 40% according to the adds. I will say they come very close to meeting their claim.

mete
September 22, 2012, 11:26 AM
It does nothing with target loads .Try to understand the physics of it.

It does help with full loads .Putting the porting at and above the center line of the bore helps reduce muzzle rise which can reduce felt recoil.

40% seems way high , 25% is more likely .I wonder how they arrived at 40% ?

Tombstonejim
September 22, 2012, 11:59 AM
I hate to ask this silly question. But if porting does nothing for target loads why are most high dollar trap and skeet guns ported?

jaguarxk120
September 22, 2012, 12:10 PM
Kolar, Perazzi, and Zoli do not come ported, although if you want porting any of the three will be more than happy to port the barrels for a slight extra charge.

Chuckusaret
September 22, 2012, 01:15 PM
I have several ported guns and it does reduce felt recoil and muzzle flip/rise. Mine were ported by Mag-na-port.

BigJimP
September 22, 2012, 01:27 PM
Its often debated on here....personally, I do think it reduces muzzle rize for your 2nd shot ...even using relatively light target loads.../ and it might reduce recoil a little ... but others say its just a marketing ploy ...

But all of my target guns ....Browning O/U's and my Benelli super sports are all ported ...at least the 12ga and 20ga's...not the 28ga or .410....

but I think the OP is wondering whether he can take a drill ...and drill bit ...to his gun and start drilling holes ...?? :confused: ....but I wouldn't suggest " do it yourself porting "...not even on a 500.../ you're going to need a fixture to hold the barrel stead, variable speed drill press, some bits that will cut the steel in the barrel ...and be able to de-burr the top and the inside of the barrel with a hone or something.. and potentially touch up the finish....

porting - is not a do it yourself project - in my opinion.

Chuckusaret
September 22, 2012, 01:48 PM
BigJimP is correct, the muzzle flip/rise is reduced by a noticeable amount but the felt recoil is reduced by maybe 5% or so. Would I attempt to port any of my guns, never. It takes more than a drill press and drill vise.

big al hunter
September 22, 2012, 04:12 PM
Mete, the flex tech stock has a very flexible core and butt pad that is surrounded by a vented shell. The combination allows a large amount of the recoil to be absorbed into the stock and released slower. Thereby reducing felt recoil. I have one on my TC Encore 12 ga. slug gun. It is close to half what I feel from my other shotguns. You should try it. :D look

tcarms.com

mete
September 22, 2012, 04:33 PM
big al , that looks interesting !

In addition to understanding the physics of the recoil we did some serious testing . Tombstone --There are many gadgets that are really scams and people who don't know the science etc are taken in .That happens in almost any field.

I was part of a test with some very good ,very experienced sporting clay shooters .Two identical Browning SC guns were used, one with and one without porting .A round of SC was done by shooting half the rounds with each gun. The shooter was asked if he could detect any difference , and the watchers were asked if they could see any difference.
No difference was seen or felt with target loads.

Pure target loads made by companies like Remington have powder carefully chosen that will burn all the powder completely within the barrel.That removes any jet or rocket effect that is reduced by porting.
The porting however will act on powders that are burning outside the barrel and reduce recoil.
It's all physics but they don't teach science in schools anymore !:(

zippy13
September 22, 2012, 10:58 PM
Pistolgripshotty,

Mossberg will port your barrel for $35. At that price, it's hardly worth considering doing it yourself.

Method
September 22, 2012, 11:43 PM
I've got porting on my competition gun. I haven't noticed a distinct difference in recoil compare to guns without the porting. What I have distinctly noticed is that cleaning a ported barrel is much more difficult with a ported barrel. I find myself with q-tips and pipe cleaners trying to get into every little hole...and even then I end up with a couple residue flakes I can never seem to get off.

Like many things (e.g. raised ribs on skeet guns), I think there's solid science and engineering behind porting...but I personally don't find the benefit in recoil reduction to justify the additional hassle in cleaning.

I would not disqualify a gun for purchase if it had ported barrels, but it is most certainly not a requirement for me, and I prefer the regular barrels.

TheKlawMan
September 23, 2012, 12:47 PM
Don't forget a major factor. They look cool! KInd of llke the old Buicks.

340 Weatherby
September 23, 2012, 06:35 PM
Klawman that's the best reason I've heard yet! LOL

PJR
September 24, 2012, 07:52 AM
Some friends tested this by swapping ported and non-ported factory barrels of identical length and weight on a Beretta 390. Using target loads we each fired 25 shots without knowing which barrel was on. Initially I could not tell the difference based on recoil or muzzle rise. Eventually I could tell the difference but only because the ported barrel was louder.

I've owned ported guns and for clay shooting I wouldn't not buy a gun because it was ported but currently none of mine are and I certainly would not spend money getting it added to a gun in the aftermarket.

TheKlawMan
September 24, 2012, 12:23 PM
we each fired 25 shots without knowing which barrel was on

How did you manage not to know?

Firefighter88
September 24, 2012, 12:41 PM
Does porting a barrel, that was originally not ported, affect the value of the gun at all?

BigJimP
September 24, 2012, 01:21 PM
If its done right ...probably not ...

If its done by some "Bubba" in his garage....yes, probably ...

If you have a barrel ported ...or any major changes in a gun done ( like going from Inertia triggers to mechanical triggers ) - I'd suggest you keep copies of the work order ( kind of like you would on a car )..especially if its an expensive gun with retail value over $ 4,000 or so .....to prove the work was done by a well known gunsmith or a reputable shop ( like Briley Mfg ) or if the original mfg did the work, etc...

PJR
September 24, 2012, 07:04 PM
How did you manage not to know?
Blocked out shooting glasses on the shooter, testing done under controled conditions. The gun was loaded with two shots and handed to the shooter who could not see which barrel was on the gun. One guy fired, one guy loaded, the third made sure the muzzle stayed in a safe direction.

g2gunny
September 25, 2012, 09:01 AM
Lots of great info, thanks for the response....helped me too!

.300 Weatherby Mag
September 25, 2012, 09:40 AM
The only ported shotgun that I haven't detested in some way is KlawMan's Browning XS skeet... Many ported guns are noticeably louder, which to me is a big drawback... I shot someone's K gun a while back that would blow fowling back at you from the top barrel to point that after a round my glasses had to be cleaned... I have no idea who did the porting on that gun, but it was pretty bad to get both fowling and hot gas directed back toward your face...

TheKlawMan
September 25, 2012, 01:57 PM
If you are going to shoot a ported barrel, try using a dirty powder like Promo. Not always, but often I get a look at a puff of smoke billowing out of the left side and it't kind of cool.

zippy13
September 25, 2012, 04:45 PM
we each fired 25 shots without knowing which barrel was on
What's important is: is your average score, over 1,000 rounds, higher with porting? You can't tell much with only 25 rounds. Only one of my comp guns isn't ported -- why, because it's one I never seem to use (it's a #2 back-up gun).

B.L.E.
September 25, 2012, 05:45 PM
Barrel ports or muzzle brakes redirect the power gasses in a direction that does not add to or even cancels some of the recoil.
These powder gasses weigh just as much as the original powder charge that generated them.

With a target load, you have about 18-20 grains of powder and 580 grains of shot. The mass of the shot is responsible for almost all of the recoil so taking that 18-20 grains of powder out of the equation will barely be felt.

With rifle loads, you might have 45-50 grains of powder accelerating a 150 grain bullet. Removing the powder's contribution to recoil will be noticable.

As you get to the 4000+ fps varmint rifles, the powder often outweighs the bullet. A 100% effficient muzzle brake could theoretically make such a gun kick forward.

A muzzle brake might be effective in a shotgun for black powder loads, where the powder charge weighs 80-90 grains.

TheKlawMan
September 25, 2012, 08:38 PM
Consider that even if the affect on porting is negligible, does that slight reduction per shot in felt recoil result in a tangible effect if you are shooting 200+ a day for two or three days in a row. One miss is the difference between winning and not winning; getting into the finals and not getting in. I think, as I am far from being a competition shooter.

B.L.E.
September 26, 2012, 05:53 AM
A muzzle brake may be noticeable with international trap loads which are only 7/8 ounce but are loaded to around 1400 fps, which means the powder to shot ratio is higher than normal target loads.

PJR
September 26, 2012, 06:34 AM
What's important is: is your average score, over 1,000 rounds, higher with porting? You can't tell much with only 25 rounds.
You can tell whether there is a discernable difference in recoil and muzzle jump. Perhaps even more so because you are focused just on the recoil of the gun. This testing as well as owning and shooting ported guns leads me to the firm belief the technical benefits of ported barrels are over-stated. But if a shooter believes that the barrel porting is breaking more targets then the mental benefits are undeniable.

If you want to improve your scores getting your barrels ported is very, very low on the list of the things I would recommend. YMMV.

Firefighter88
September 26, 2012, 08:54 AM
Although I think we have strayed from the OP, I will add my two cents. I have learned in other aspects of competition, that the very fine details and differences that affect performance for the better or worse are only noticed by the more experienced individuals. I am an amateur when it comes to guns, and porting may not affect my performance at all, but when you get to higher levels of competition, EVERYTHING affects performance. I may not even be able to tell a 20 guage from a 12, if blind folded. I bet a professional could(or even experienced amateurs). If you change anything with the gun, drill holes in the barrel for instance, things change.

zippy13
September 26, 2012, 03:17 PM
What's important is: is your average score, over 1,000 rounds, higher with porting? You can't tell much with only 25 rounds.
You can tell whether there is a discernable difference in recoil and muzzle jump.
It's often the indiscernible differences, the very subtile changes that can make a difference in performance. My scores are higher, especially in all-doubles events, with ported barrels. YMMV.

PJR
September 26, 2012, 05:13 PM
My scores are higher, especially in all-doubles events, with ported barrels.
Is the gun one that you added porting to and changed nothing else? If so then you can make the point that porting is giving you better scores. But if it's a different gun, different stock, different load or some other change then any or all of these factors may equally be part of the improvement if not greater.

zippy13
September 26, 2012, 06:53 PM
Is the gun one that you added porting to and changed nothing else? If so then you can make the point that porting is giving you better scores. But if it's a different gun, different stock, different load or some other change then any or all of these factors may equally be part of the improvement if not greater.
PJR, FYI:
Both barrel sets of my Beretta 682x were ported after a ShockMaster was installed.
Perazzi Mirage was ported before the addition of the JS Air unit.
Perazzi SC3 was ported by the factory but has custom wood.
Perazzi MX8 is non-ported but has custom wood.
Remington 1100T (rainy day gun) has only been ported (2 barrels).

Only the 1100 has factory wood, the others have been altered. With my primary comp guns having recoil reduction systems, there isn't a noticeable change in recoil; however, I do feel that I can get on the second shot quicker with the ported guns. I've been using the same recipe reloads for years. As you mentioned earlier, it's hard to know how much is between the ears.

TheKlawMan
September 27, 2012, 08:28 PM
I am guessing that there is a difference between what you consciously recognize to be more recoil and what your body subconsciously recognizes.