Does barrel porting do anything on a low pressure cartridge?

[AbitNutz]

I've been a fan of Magnaport for a long time. I've had 4 guns done, all with excellent results, 357 magnum Python 6" inch (40 years ago), Freedom Arms 454 casull 4-3/4", LAR Grizzly 45 win mag 6-1/2", Ruger Blackhawk 300 gnr 7-1/2" (like a 30 Herrett, made from 30-30 cases. I can't recommend Magnaport highly enough for what it does as well as turn around time and overall customer service.

The muzzle flip reduction was dramatic in all of them. However, all of these are very high pressure cartridges. I just put together a Para Ordnance long slide in 45 acp. As we all know, the 45 acp is anything but high pressure. I'd like to try the through-slide porting that Magnaport offers but I'm wondering if it will do much at all since the 45 acp only runs at 16,000 and not double or even triple that of the others.

Your thoughts please.

[pietro]

.

Be it large
Be it small
Magnaport
Will reduce them all






.

[DougGuy]

I had a 5" magnaported 1911 on a Para 13+1 frame I used for pins. It worked. If you load to +P you will notice more effect from the ports.

[AbitNutz]

I'm really proud of this particular pistol so I'm going to have it Magnaported. It's a Para Ordnance long slide, wide frame. It is stupid accurate. I owe that to a couple of things...none of them me.

1. I used a Caspian ghost ring adjustable rear sight and a Dawson fiber optic front. I've never seen this kind of rear sight before. The sight picture is awesome and fast, very fast.

2. Briley barrel bushing. They are the best.

3. Kart Exact Fit barrel. I'm sure other barrels are just as good but the Exact Fit let me accurately fit it myself.

4. Wilson barrel links. I was able to choose the exact length barrel link.

5. Guncraft trigger

6. Deleted all the series 80 paraphernalia...get it? Para-phernalia...sometimes I crack myself up.

7. Longer sight radius with the wider (.125) front sight lets me get a great sight picture.

8. Hogue finger grips. While they look stupid they force my hand to stay in the same position.

I've been really lucky with this pistol. Not only is it wonderfully accurate and easy to shoot, it also just refuses to jam. I use an EGW PXT extractor in place of that idiot Para-Ordnance affair. If I were to have problems with extraction I would insert the reduction sleeve I have and use an AFTEC extractor. That'll peel the top off a beer can. I also have a Dawson extended ejector. It throws the empties into a nice, meat pile.

Sorry for bragging but I just really like this pistol. It's my first long slide.

[DougGuy]

You might have issues with that Briley bushing right off the bat. It fits so snug that the barrel will get powder residue on it and if you are shooting cast, it will get lube residue and I don't know how long it will run without cleaning.

[AbitNutz]

That's an interesting point I hadn't considered. The barrel is .580 and the bushing is .581...And I do shoot cast. Who with a .45 auto doesn't?

The bushing is titanium nitride and pretty slick...maybe it will just glide right over it...but probably not.

[AbitNutz]

I called Magnaport first and explained what my concerns were. They said they make the ports oversize so that virtually none of the fouling ends up on the barrel. They also said they port about a zillion automatics of all grades and never had an issue...well, what would I expect them to say? So I called Briley and spoke to them...the guy I finally got to told me he has a 1911 that has been Magnaported and he uses, as one would expect, a Briley bushing, and never had a problem...well. There's a lot riding on this when you consider the cost of a Para Long Slide, a Kart barrel and Briley bushing will not work as I had originally intended.

[gwpercle]

The ported barrel on my 45 acp revolver seems to lessen recoil and hold down muzzle rise.
I can't prove it , but it certainly feels that way to me !
Gary

[AbitNutz]

I was able to shoot two identical 357 mag revolvers side by side. The difference was dramatic...and I mean dramatic, no doubt what so ever that Magnaport reduced the muzzle flip and not just by a little...it was a lot!

[DougGuy]

The higher the pressure the more effective the ports are. A 357 is a LOT higher pressure than a .45 ACP so yes it would be dramatic. If the guy at Briley uses their bushing with magnaported barrel I'd say go for it. I have used a couple of their bushings and love them. I just didn't know if they would get fouled but I guess not.

I currently have a Mossy 500A with a 20" pro ported barrel, the heavier the loads the more it works. I can rapid fire hot loaded #4 buck with about 3/4" max muzzle flip. It's back on target immediately. I was shooting it on the local indoor range when I lived in Virginia, and at 7 yards I managed to snap off 3 shots before the muzzle blast got to the target and caused it to flap up in the wind so I couldn't see it any more, there were a bunch of Va. Beach cops on the range that day and they all came over to see what I was shooting. They were quite impressed. This is NOT a shotgun you want to hold down by your hip and fire it.

[AbitNutz]

I just think I hit the magic combo *for me*, Long slide, double stack .45, ghost ring rear sight. This gun just checks all the boxes for me. I'm going to Magnaport it.

I can see in the pictures that the ports in the slide are significantly larger than the ports in the barrel.

[bob208]

back when I was shooting bullseye on a indoor range. I was using a ruger mk1 .22 each shot it would move the sights off of the black. I put a muzzle break on and it would stay on the black.

[beezapilot]

I had a Springfield XD in 9mm with a ported barrel and a slotted slide- thing wouldn't cycle / eject on about 15%of the rounds, got a solid barrel and had no further problems.

[AbitNutz]

I wonder if that screwed up the slide weight/recoil spring ratio?

[AbitNutz]

I'm going to tune it to shoot 45 Super. I ordered 500 rounds of Starline brass and some 185 gr Sierra FPJ & Hornady XTP bullets. The Kart barrel is as good as it gets. I got it locking up with a snap on a #4 Wilson link. I've got a Wolff Long Slide spring coming so I can tune it. The loads I've been looking at say I can get 1300 fps easily on a 5" barrel. A 6" adds about another 100 fps but Magnaporting should drop that about 50 fps. So I should get a net gain of something over 1350 fps.

I've got to get the Hogue grips fitting better... I love them but they hang up on the trigger stirrup somewhere.

[Cap'n Morgan]

The efficiency of barrel porting in reducing muzzle flip and recoil is depending on muzzle pressure and powder weight. Porting a shotgun barrel where a 500 grains payload is propelled by 25 grains of powder and the pressure at the muzzle is less than 500 psi, is a waste of money. On the other hand, in a rifle cartridge with a 150 grains bullet on top of 70-80 grains of powder and a muzzle pressure of 12000 psi (that's well over the max SAAMI chamber pressure for a shotgun) porting can make a huge difference, but so can a muzzle brake or a suppressor.

I doubt ordinary Magna-Porting would make any significant difference in a 45 ACP. Probably better to mill some large slots on top of the barrel and slide.

[AbitNutz]

I doubt ordinary Magna-Porting would make any significant difference in a 45 ACP. Probably better to mill some large slots on top of the barrel and slide.

I think you're probably right about that. I've seen/read a couple of tests where a ported 45 acp had muzzle flip reduced only about 10%...not much.

I'm going to go down the 45 Super route, which runs into the range of 32,000 to 38,000 instead of the 45 acp which tops out at 22,000.

I think a 185 gr bullet moving at 1,350 fps out of a ported 6" barrel should generate a fair amount of beneficial pressure...no?