what is the difference between ported barrel and comp'd barrel???

[Centimeter]

sqlbullet, can I ask where you go those numbers for weight values? The one I have experience with, the Lonewolf one I cited above, weighs in right around an ounce and a half according to LW. Even their biggest ones, for "major" 9mm, only weigh 2.5 ounces. Also: typical two-slot porting wouldn't reduce barrel weight by 10-15% (given a 5oz barrel weight) unless you're also figuring the weight of the area cut from the slide to allow for the porting. If you're talking about a full-length port job with four to six ports, then certainly the weight might be reduced upwards of 20%, but you also have to account for the huge section of the slide that has to be cut out of the top of the slide to accommodate those ports, thus negating substantial amount of weight from the slide.

[sqlbullet]

Let me address those in reverse order.

.5 to .75 oz difference for a ported barrel.


This is for an extended barrel versus a stock barrel.  The difference is increased weight in the ported barrel, as the ported barrel would be a 6" rather than a 4.6".  The assumption was starting with a standard Glock 21 non-ported, and adding a ported barrel to it.  The weight was estimated based on 5" barrels I have weighed being around 5 oz weight.  About half that weight is the chamber area, leaving 2.5 oz over 4" or about 5/8 oz per inch.  If we are comparing a stock Glock 21 to a stock Glock 21C to Comp'd Glock 21 then the relative weights would need to be re-evaluated.

Compensator Weight


I googled Glock compensator, found the lone-wolf 460 rowland comp and looked at shipping weight (.317 lbs = 5.072 oz).  You are correct in assuming that this was a wag.

Subbing in a 1.5 oz weight increase for the comp, we see a smaller reduction of about 8% in slide velocity (39 to 36 fps slide velocity).

These numbers are in no way "accurate".  They are based on a hypothetical model, using mainly slide weights from my para P16-40. They are intended specifically to clarify that a comp will definitely slow down the slide measurably.

If someone wants to post up actual slide and barrel weights on a Glock 21, Glock 21c, 6" LW ported barrel, LW threaded barrel that a comp would attach to I would be happy to run the numbers for a Glock.

[Centimeter]

Ah, understood, that makes sense. Thank you for the clarification; I was curious about your estimation for the ported barrel as I was assuming you were talking about a Glock OEM barrel with factory porting ("C" models) which I now understand you weren't.

I do agree that an extended, ported, barrel would definitely weigh more, almost certainly by the amount you estimated. In your estimation would an extended ported barrel produce anything different, numbers-wise, from an internally ported barrel knowing that internal ports require a corresponding weight reduction in the slide due to the necessity of opening the top up? It almost seems like they'd balance each other out, really coming down to a choice of personal preference. All in all, again, I think that a compensator will definitely do "more" for reducing muzzle flip and felt recoil/slide velocity than porting alone be it OEM or aftermarket.

[sqlbullet]

Here is how I see it.  We are really talking about two measurable impulses, perceived as mechanical recoil.  They are barrel flip and slide velocity.

Glock 21 is baseline.  values x for muzzle flip  and y for slide velocity.

Glock 21c.  X will be reduced by the venting of gases upward during firing, but Y will increase as the barrel/slide mass is reduced by material removed.

Glock 21 + 6" ported barrel.  X is reduced by venting of gases upward during firing, and Y is decreased overall due to increased barrel/slide mass of the longer barrel.  The "overall" part is because the slide does accelerate for some extra time here due to the longer barrel, but not enough to make up for the increased mass.

Glock 21C + 6" ported barrel.  Again X is reduced by the venting of gases.  I cannot speak to Y as I have no data regarding the mass of a ported slide and mass of the 6" barrel.  If the barrel/slide mass is less than stock, Y goes up.  Less than stock, Y goes down.  I would guess this will be pretty close to neutral for Y. 

Glock 21 + comp.  Best of both worlds as you are adding a good bit of mass, as well as venting gas.  Meaningful reductions in both X and Y.

[Centimeter]

Excellent breakdown. That's about how I was figuring it as well. All things considered, I would think that the stock setup with the addition of a compensator would produce a statistically significant difference in both slide velocity and muzzle flip, more so than factory or aftermarket porting, while maintaining at least, or more, mass overall. Mass is clearly the most crucial variable in reducing slide velocity.

Is there any kind of "Handgun Pull-Down" available?? Might be cool to actually get some accurate weights and measurements of the different components out there. It would be interesting to see just how much of a difference there really is between all the options so we can better approximate their effects when put into use.

[sqlbullet]

There isn't.

I have long thought it would be cool to put up a good firearms wiki site.  It is really a better format for that type of information than a forum.  Maybe I will try to get motivated over x-mas.


Edit--

There is this:

http://guns.wikia.com

But it is so commercialized that I can't stand it, and the information is really limited.

[Centimeter]

Ah yes, the ever-present Wiki! I knew there had to be at least one dedicated to firearms, especially since there's one for just about everything else. The community-editing part would definitely make it much quicker and more efficient, even with a relatively limited moderator involvement. It's a shame that one is so heavily laden with commercial interests, though. Perhaps if you're motivated enough you could start with a 10mm-Wiki! 

[billlyb]

g24 c ported barrel

[sqlbullet]

Can you weight the slide and barrel, preferably separately, and post their weights?

[The_Shadow]

billyb, very nice looking setup!   

[billlyb]

sure might take a few to find a scale    an its a 40 cal   ( short 10 mm )

[gandog56]

Am I wrong? I thought either a comp or porting made the darned thing LOUDER!

[sqlbullet]

Am I wrong? I thought either a comp or porting made the darned thing LOUDER!

A comp is a ported weight.  Both make the gun seem louder to the shooter as they redirect the energy up, rather than forward.

[Pinsnscrews]

Just to be silly, can I get an extended barrel with ports and a compensater attached to the slide 

In theory, if you get it timed correctly, and matched the cuts, you would create longer ports with the two.

I just haven't seen anyone do this in a manner that would compliment each other. What I have seen is a ported match barrel with matching slots in the slide and a solid, non-ported compensater attached to the slide of a 1911 in 9mm. This does not mean that someone hasn't done it, just that I have not seen it done yet.

[gandog56]

I've seen ported (Or is it comp'ed) bushings you can put on a 1911. Have no idea if they actually do anything, though.