After acquiring one of the new Brownell’s LW 1 - 12 twist barrels I decided to review in comparison to a retro Colt model 604 build with 1-12 twist C MP Chrome Bore barrel with a fairly low round count for dimension, finish, attention to detail and accuracy using Federal M-193 and reload ammo.  Most everything I used for the testing is available from Brownell’s, an AR15.com site vendor and one the largest sellers of firearms parts, armorer’s tools and reloading components for the shooting enthusiast.  

For the barrel testing I used a current production Anderson Mfg A-2 lower receiver with a massaged Colt FCG and Colt M-16A1 type D stock assembly for the bottom and SP-1 upper receiver with front pin adapter bushing,  NOS Colt M-16 BCG and CH.

The barrel I received from Brownell’s was laser engraved under the HG’s MFR 12238 MP Chrome Bore 1-12.  It is magnetic particle inspected 4140 steel, chrome lined barrel and chamber with a 1-12 twist rate that has been proof tested using Black Hills ammo to 70-73,000 CUP.  The F marked FSB was installed using taper tins.  The barrel I received was shipped less sight parts and sling swivel.  The barrel has a non-ramped extension.

Physical dimension of barrel and finish compared to the Colt is very close.  Both were machined from .980 blanks and contours are very close throughout length.  The Colt barrel measured .675 from taper to FSB where the Brownell’s item measured .605.  The Brownell’s barrel is slightly lighter in overall weight.  Both measure .626 at FSB and beyond FSB .568 Colt and .572 Brownell’s. The Colt barrel has a more green hue and is lighter in color compared to the black phosphate finish on the Brownell’s item.  From 5 feet indoors they look basically identical.

Install went very smooth.  Barrel was as clean as any I’ve ever received with no metal shavings or grit to be found anywhere.  Headspace was good and after usage I found the chamber was very brass friendly with little to no case stretching, a plus for the reloader as less case trimming means longer brass life expectancy and less labor intensity.

Actual performance and accuracy testing was done at 50, 100 and 200 meters.  Unfortunately on first test day I was treated to 30 MPH swirling winds and my hat goes off to those living and shooting in the windy regions.  Definitely something I need to work on as I was continuously chasing my groupings away from the 10 ring.  5-10 mph winds is normal but both the wife and I could hear the wind howling with ear protection and I couldn’t adjust for it as wind direction was constantly changing.

After a quick zero I went to work on the targets.  First day retro test I fired over 200 rds through the Brownell’s barrel and put another 50 plus through my Colt 604 retro clone that had previously been zeroed for 100 meters.  The Brownells’ barrel I ran CLP and patches through every 40 rounds.

I found the Brownell’s barrel performed better with the higher velocity ammo.  Guessing wind was a factor but it didn’t like lower end of spec / velocity what I call plinking ammo for best accuracy.  Lighter load ammo cycled fine just didn’t provide groupings I was looking for.  

I initially ran 60 rounds of LC factory M-193.  It performed flawlessly but 2.25 in. 10 shot group was the best I could do with it on that day.  The Colt barrel was a tad better around 2 in.  I then switched to reloads and for me the hotter rounds performed best.  I tried Hornady 55-grain FMJ,  Mid-South 55- grain HP and 52-grain SMK HP bullets over CFE223, H-335 and Varget powders.  For me the CFE223 at 27-grain plus/minus a 1/10th or two was the most accurate yielding just under 2 in groups with the Brownell’s barrel and a 1.75 inch best using the Colt.  No excuses for the wind but I usually do a little better or more in the 10 ring.  I tried various COL’s but .2230-.224 seemed the most accurate out of the Brownell’s barrel.  The Colt upper  likes them a little longer 2.25-2.26 generally.  Primers used were Rem 7 ½ and WSR.  At 200 meters I was shooting a little high without sight adjusting and groups opened up to 4 - 5 inch or so.  At 50 meters most every shot was in the 10 ring.

Really no disappointments or hiccups.  Mag used was a Brownell’s straight 20 round that now has 3K through it with no malfunctions to date. Spent some quality together time with the wife, doing what we enjoy.  Shooting in the boonies away from the hustle and bustle on Easter weekend.



 

After testing on the Colt SP-1 upper receiver I removed and installed the Brownell’s barrel on a flat top non-ramped upper receiver for shooting with an optic to see how it performed.  The optic used was a Vortex Crossfire II 4x12x44 # CF2-31015 on a Burris AR P.E.P.R mount.  

For the second day the wind calmed down a bit and was able to shoot another 200 plus rounds.  Basically more of the same, using LC factory M-193 and reloads.  

With the optic I was a bit more consistent but didn’t really reduce grouping size.  Closer to the center but spread remained constant.  Again faster velocities were the most accurate for me.

For a retro replacement barrel or for a scoped flat top light weight, the 1-12 twist barrel complete with FSB installed has been a niche item the AR platform community has long desired.  I’d definitely recommend this item.  I wouldn’t compare it to a match rifle barrel but its weight savings and slower twist rifling make it a rather handy field piece for various shooting environments.  





Bottom three 50 meters,  top left and center 100 meters and top right 200 meters.  These represent 25% of actual shooting and were the best targets.  Not sure test is accuracy conclusive as I've really never done much 30 mph wind shooting and as stated I adjust and wind would shift the opposite direction. Almost frustrating but I didn't let it get me down.   Wife and I had some good together time but I really was worn out at the end of day two and didn't take camera for 200 meter pics and was too tired to walk back and get it.  Field is 23 acres cleared and I was actually walking to inspect longer range  targets so I logged a few miles on the boots before it was all said and done.

Thanks for the review.

Thanks for the review Cden, we still need to get together at some point! I believe I owe you some range time.

That's a great review, and I think you went above and beyond at making it as extensive as you could, particularly with the installation on a flat top with scope.

If you want to shrink your group sizes, lap the receiver faces with the Brownell's tool, and use Blue Loc-tite to bed the barrel extension into the upper.  It will surprise you what will happen with accuracy.

So far, it has shrunk group sizes in half every time I do it.  It's also better for your bolt life to have a square receiver face.

Awesome review, thank you for taking the time to conduct and write it up!

Cdenmark, Thanks for that review. A good read and good getting to see how someone else goes shooting. Looks like the windy conditions didn't interfere with getting results. Those groups look really good for 100yds. 200yds is impressive too. Above and beyond, for certain.

Excellent. Thx! I'll pass the word.

Cdenmark, Nice review of the Brownells barrel. Looking forward to further information as you get a chance to shoot more.

nice write-up  

thanks

A good read and good getting to see how someone else goes shooting.

I use the old, worn blankets and sheets to save / find fired brass in the grass and less ticks.  None this trip.  One sheet for me and one for the brass. Old 5th Crown sacks (free from neighbor) are for spent brass.  Craftsman tool bags at $5 per for shooting bags.  Cheap $3 Walmart Outers target stand.  I also use 12x20 wood sheets with stapled targets but I'm running low on those.  Shooters Ridge sand bags.  I keep a bayo lug bipod but some barrels don't like it.  Most all my shooting is prone or I have a pile of cinder blocks I can cobble a sitting bench.  Standing I prefer to lean against something like a tree.  Figured with the wind it was best to stay as low as possible.  I'm a fair weather shooter now days so Howling Winds was a little different atmosphere.

I hope to do some more in near future.  200 meter target is dated 1985 from small bore days.  Only have one left.  How time flies! I also had some groups that resembled the 200 m at 100 m.  Again I know virtually nothing about reading the wind but my 604 is closer to 1 MOA than not usually.  It has Young and other NM components hidden inside the mottled sheeps clothing.  Wife almost lost my homebrewed shell deflector.  Luckily I saw it on final walk through.  It's probably covered 70 miles on foot and she knocks it out on one rifle pick up.