Barrel choices and why? Lookings for experience and recommendations!

[mellino19]

Hey all,

I'm one of those guys who can't leave anything alone with my rifles and recently have been toying with two or three different ideas in terms of upper receivers and barrel options. For the past year and a half or so I've been running a 16" JP barrel with a venom defense muzzle brake so maybe my OAL is 17.5"? I also have a 14.5" with a 2.5" MBX-style comp as a backup upper.

 

I was considering building an 8" PCC upper to install on my SBR and use a conversion mag block but then I got to thinking more on this, do I just get an 8" shroud from Taccom and have a lighter upper or do I abandon the whole SBR thing and look at the pistol length barrels with the shrouds to be compliant 16" and super light? (like the JP lightweight, Wiland LLW, and Taccom barrels with 5" rifling following by the extension)

 

So my main question since I know everyone has different thoughts on this:

-Stick with the 16" franken-JP upper?

-Build an 8" SBR upper for in-state fun (and hassle when wanted to take it out of state for area matches)

-Build an 8" upper with an 8" Taccom extension to be 16" and legal all over?

-Go completely different with a Wiland/Taccom ultra light weight barrel? - I could run my CO loads in this and not have to make two different loads as well.

 

What do you typically run and why? What have had you best results with?

Edited October 29, 2019 by mellino19

[zzt]

I more interested in transition speed for Steel Challenge.  It will also help if I decide to use it for USPSA.  I kind of doubt it, because I love Open so much.

 

I need a 16+" barrel, because it is legal everywhere and I don't need a stamp..  I'm going with the WilandUSA LLW barrel.  Although it weighs 15 oz., the weight is concentrated near the receiver.  The barrel is 5.5", so I don't get the increased velocity (and recoil) I'd get with a 16" barrel.  Since there is no comp, I can shoot less expensive coated bullets without worrying about crudding up the comp.

 

I've tried 19 oz. pencil barrels.  They swing slow.  I was going to go with a BSF carbon sleeve barrel at 16 oz., but that is not much of an improvement.  The Polar Moment is not as good as the LLW.  There are two things that decided me on the LLW.  The first was my newest Open gun.  It is heavy with a SS grip.  Everyone said the transitions would be slower than with my lighter poly grip guns.  I set the gun up so it balances on my left index finger, so really all the weight is between my hands.  I'm faster with this gun than I was with the others.  Why?  It doesn't feel muzzle heavy.  Now my other guns feel like I'm swinging a log.  The second was how much faster my transitions were with my full race, light Buckmark over the 1911 with conversion I have been shooting.

 

So my recommendation would be one of the ultra light barrels you mentioned.  I went with the LLW because the rifled barrel is longer and IMO the build is better.

 

FWIW, I like the concept so much I have an LLW 22 11 oz. barrel on the way for my RFRO gun.

[Norther]

I have an 8” CMMG Guard, and a Taccom ULW. I find the Taccom stays in the safe now. 

[mellino19]

Thanks @zzt, lots of great insight and I do like the idea of moving the weight back for transitions and not wanting to deal with a Form 1. Everything I have heard of the Wiland has been positive so far. I agree with the coated bullet part as well, I currently run Blue Bullet 125gr RN through my 16" with the comp and after a few hundred rounds of course I start getting build up and have to chisel it away. Todd over at Wiland also said the action tends to stay cleaner longer because of the lower pressure in the barrel so that's another enticing aspect of this style barrel.

 

@Norther is your Guard an SBR or is it 8" with an extension to be 16" OAL? Why leave the Taccom in the safe now? Other than if it is an SBR, navigating a stage can much easier with a shorter barrel. As I mentioned I could slap the 8" on my AR15 SBR and put the glock mag conversion block in to achieve this although reloads on classifiers will becoming a little tougher with a different mag release setup.

[stick]

I have three PCC's  All three have Taccom barrels.  One has the ULW with Aluminum shroud.  One has the ULW with Steel Shroud and one has the 13" Featherlight with comp.  

I would suggest you find one setup that you like and stick with it.  I gave the aluminum shrouded gun to my daughter, the steel shrouded gun was used for steel challenge and the 13" is used for USPSA.

[Norther]

 

4 hours ago, mellino19 said:

@Norther is your Guard an SBR or is it 8" with an extension to be 16" OAL? Why leave the Taccom in the safe now? Other than if it is an SBR, navigating a stage can much easier with a shorter barrel. As I mentioned I could slap the 8" on my AR15 SBR and put the glock mag conversion block in to achieve this although reloads on classifiers will becoming a little tougher with a different mag release setup.

It’s an SBR. I just like the gun better. PCC is a “just for fun” division for me, and SBRs are fun! I built the ULW too light I think. 

 

You will still get coated bullet build up inside the shroud of an ULW. There are various techniques people use to get it out, discussed here somewhere. Builds up significantly though. 

[zzt]

3 minutes ago, Norther said:

You will still get coated bullet build up inside the shroud of an ULW

 

Is that with all coatings?  I don't see the coating getting flame cut like it would in a comp.

[Norther]

There was a fair amount of discussion a while back. People were trying hole saws on extensions, or filing teeth into the end of a piece of conduit etc. I only tried Blue Bullets, and there was build up. I got most of it out with some copper wool wrapped around a 12 ga bore brush. I could see it being a problem if you shoot a lot. 

[mrd]

18 hours ago, zzt said:

The barrel is 5.5", so I don't get the increased velocity (and recoil) I'd get with a 16" barrel. 

 

Is this really correct? Recoil, as far as I know, is generated by the impulse from the combusting powder load - not the energy/velocity generated into the bullet. With a longer barrel you can use less powder to achieve the same power factor, and thus have less recoil. Also, a longer barrel generally have more weight, which also absorbs recoil.

 

However, if you use a comp, a shorter barrel can be better because there is higher pressure in the gas generated to work the comp.

 

Correct me if I'm wrong, I'm here to learn as much as most of us.

 

 

[Les Snyder]

have you thought about one of the CMMG radially delayed bolts/barrels?.... I've been playing with one for about 6 months now, and after some experimentation with modifications to magazine followers, like that it cuts a lot of reciprocating weight out of the bolt and carrier... with a 142pf Bayou 135 load, hydraulic buffer and modified Miculek comp, I get the least amount of dot movement in the over 3 years I've been shooting a PCC... compared to L9x25's aluminum shrouded blow back with 100 grain bullets, I get negligent dot movement similar to his... his light barrel is easier to swing, but his recoil impulse is straight back and more noticeable, but the end result of no dot movement is about the same

 

at 72 I'm low speed and high drag, so my carbine is not the limiting factor in my performance, but it is fun to attempt to work out problems... regards

[zzt]

3 hours ago, mrd said:

Is this really correct?

 

Yes.  The formula for recoil is E=(Bw x Mv + 4000Pw) squared / 64.348 Gw  when Bw is bullet weight, Mv is muzzle velocity, Pw is powder weight in lbs. and Gw is gun weight.

 

You see that Mv and the other values inside the parens ar squared.  So changes to any of those values has an outsided effect.  For example the same load that makes 1300fps of of a 16" barrel makes 1050 out of a 5" barrel.  1050 squared is 1,102,500.  1300 squared is 1,690,000, and significant increase.

 

Powder weight in pounds makes a little difference.  Say the difference in charge weight is 0.2 grains.  That is 0.0000285 pounds.  Squared that is 0.000000000816.  So you see it makes little difference.

 

Chamber pressure does not 'work the comp.  Gas volume does.  The more gas you generate, up until some of it jets out the front, the better the comp 'works'.

 

I want to use light loads, commercially bought if possible.  So the shorter barrel is the way I want to go for two reasons.  First it will swing better.  Second it will give me pistol velocities out of a 5.5" barrel.  The commercial 115 @ 950fps out of a 4" barrel grows to 1200fps out of a 16".  A third reason is there are many bulged barrels because of trying to shoot a low PF load out of a 16" barrel.   A round soesn't make it out of the barrel and the second hits it and bulges the barrel.  There was a recent post here about a guy using an 11" barrel.  It was cut down from a 16" because a bullet didn't make it out and the next bullet bulged it.

 

 

 

[mrd]

13 minutes ago, zzt said:

 

Yes.  The formula for recoil is E=(Bw x Mv + 4000Pw) squared / 64.348 Gw  when Bw is bullet weight, Mv is muzzle velocity, Pw is powder weight in lbs. and Gw is gun weight.

 

You see that Mv and the other values inside the parens ar squared.  So changes to any of those values has an outsided effect.  For example the same load that makes 1300fps of of a 16" barrel makes 1050 out of a 5" barrel.  1050 squared is 1,102,500.  1300 squared is 1,690,000, and significant increase.

 

Powder weight in pounds makes a little difference.  Say the difference in charge weight is 0.2 grains.  That is 0.0000285 pounds.  Squared that is 0.000000000816.  So you see it makes little difference.

 

Chamber pressure does not 'work the comp.  Gas volume does.  The more gas you generate, up until some of it jets out the front, the better the comp 'works'.

 

 

Interesting. Where did you get the formula for recoil from?

 

I don't mean chamber pressure, which refers to max pressure during combustion. I mean the gas pressure inside the bore of the barrel, just when the bullet exits the barrel. 

 

The gas volume works the comp only so far as pressure being a function of gas volume vs bore volume. Same load works the comp better in a short barrel compared to a long barrel. The gas volume is the same in both barrels. However, pressure is lower in the longer barrel because the gas volume is spread out in the larger volume of the longer bore. Also, a longer barrel cools the gas more and decreases volume and thus pressure. 

[zzt]

6 minutes ago, mrd said:

I mean the gas pressure inside the bore of the barrel, just when the bullet exits the barrel. 

 

It is not pressure in the bore that works the comp, although for a given amount og gas, higher pressure is better.  However, it doesn't work that way in real life.  It is the volume of the gas generated that counts.  For instance my major load of 7.2ge Silhouette is much higher pressure than my 10.2gr Major Pistol.  The MP load shoots much flatter and softer, because it gererates more gas.

 

The formula was from Winchester.  Hodgdon uses the same formula except for using 4700Pw instead of 4000.