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Posted: 3/17/2016 2:42:24 PM EDT
I recently decided to do a review of the accuracy of two of my barrels in my collection.  The first is a BCM lightweight (non-CHF) 14.5" Midlength with a pinned BCM comp, the second is a Daniel Defense lightweight (CHF) 16" midlength with a Ranier Arms XTC comp.  


The Rifles:


The BCM upper I purchased direct from BCM a couple years ago.  It came with a Centurion rail and a BCM BCG.  


image by Photographer  Pilot, on Flickr


The DD barrel I purchased from Rainier Arms as a complete upper, from their "combat series" line.  It came with a Samson/Rainier Evolution Rail and a Rainier Arms BCG.  


image by Photographer  Pilot, on Flickr


Both uppers have their barrels free floated, both using a rail system that uses a stock barrel nut, and both barrels are of the Lightweight variety. Both the DD and BCM have a .625" gas block journal.  









The Ammo:


image by Photographer  Pilot, on Flickr






For the test I selected three different types of ammo.  Federal American Eagle 55gr M-193 clone, Federal American Eagle 50gr Varmint and some handloads consisting over 77gr Nosler CC over H322.  These handloads are typically just under sub-MOA with my Larue Stealth.  It's the ammo I used for my entry in the sub-MOA thread.  


I chose these loads as I figure that M-193 is one of the most common rounds for people to use, the 50gr Varmint is a consistent performer for many people.  And I used my 77gr handloads because otherwise someone would complain about using 50-55gr in 1:7 twist barrels.  


The Setup:


I shot 3 10-shot groups of each of the above ammo, through each rifle at 100 yards.  To keep things consistent, I mounted each upper on the same lower, which has a SSA-E trigger.  I mounted my Leupold VX-R Patrol 3-9X scope, which is mounted in a Larue mount.  I used an Atlas Bipod for the test, and a rear bag as well.  After shooting all of the groups, I measured the extreme spread (outside of the grease ring), then subtracted .224 to get the center to center number.  I then averaged the 3 groups.  No shots were thrown out.  What I shot, is what you see.  


The M-193 test I shot from a bench, the others were shot from prone off the bipod.  


Prior to starting the M-193 test, I used some PMC X-Tac 55gr to get a rough zero for the test.  Each upper got it's own zero.  The Daniel Defense barrel needed 1.8 mil of elevation, and 1.2 mil of Left windage for it's setting. The BCM I left the elevation at 0, then dialed in 1.2 mil Right windage it's settings.  


The M-193 was shot last week, the 50gr Varming and 77gr Noslers were shot this morning.  


One of the rifles, as shot.


image by Photographer  Pilot, on Flickr





The Results:


First, let's start with the M193


The BCM's groups were:


3.666"
3.462"
3.520"
Average 3.549


The best group:
BCM M193 by Photographer  Pilot, on Flickr


The Daniel Defense groups were:


3.471"
2.576"
3.957"
Average 3.334"


The best group:


DD M193 by Photographer  Pilot, on Flickr













Prior to shooting the AE Varmint and 77gr Noslers, I shot 2 5-shot groups with my Larue Stealth using the 77gr Nosler handloads.  That way the test wouldn't be shot cold.  The groups measured 0.848 and 1.061"











American Eagle Varmint













The BCM Groups:


1.870"
2.148"
2.601"
Average 2.206"


The best group
BCM American Eagle Varmint by Photographer  Pilot, on Flickr


The Daniel Defense Groups:
2.466"
0.970"
1.940"
Average 1.792"


The best group:
DD American Eagle Varmint by Photographer  Pilot, on Flickr


Nosler 77gr Handloads


BCM
1.734"
2.258"
1.684"
Average 1.892"


The best group


BCM 77gr Nosler by Photographer  Pilot, on Flickr


Daniel Defense:







2.504
" 1.501"
1.199"
1.054"
Average 1.585"  1.251"




















The best group
DD Nosler 77gr by Photographer  Pilot, on Flickr
 



















image by Photographer  Pilot, on Flickr






 
Link Posted: 3/17/2016 2:54:06 PM EDT
Well it's a good thing I have BCM and DD uppers in my collection
Link Posted: 3/17/2016 3:07:40 PM EDT


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Quoted:



Well it's a good thing I have BCM and DD uppers in my collection
View Quote





 
Always good to have variety.  








I had gotten the Rainier upper with the DD barrel as a backup, and it's never been a favorite.  I've always had this perception that it was less accurate than the BCM uppers I have.  So it's kinda always just in the back of the safe.  




Might have to change that now.  

 
Link Posted: 3/17/2016 5:40:46 PM EDT
You may get even better groups if you swap out the bi-pod for a proper front rifle rest, has been my experience in the past.
Link Posted: 3/17/2016 6:00:40 PM EDT



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Quoted:




You may get even better groups if you swap out the bi-pod for a proper front rifle rest, has been my experience in the past.
View Quote






 
True.  Or I could lock it into a sled and remove any human interface.  One of these days, I will probably purchase a rest, but I like to practice from the prone, and it's very possible to get very consistent results with proper technique.  










That's why I shot 2 control groups prior to shooting the test.  I shot my Stealth upper on the same lower, same scope, same bipod and technique as in the test.  










With that setup, and ammo, I am averaging about .925 MOA.  Today's control groups averaged .911 MOA, so right about where I should be.




 



Probably, a better expense would be a different scope, either more magnification, or a smaller reticle.  
Link Posted: 3/17/2016 6:39:17 PM EDT
I've got a 14.5 mid lw upper from bcm.  It is 4 or 5 yrs old, but pretty sure it has a .625 gas block journal.  It wears a thermal scope now, but when it had a razor 1-6 on it, it would shoot 40 gr vmax fiocchi into 5/8-3/4" 5 shot groups at 100.  M855 was usually sub 2" 10 shot and m193 was about like ur results.
Link Posted: 3/17/2016 6:48:08 PM EDT

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Quoted:


I've got a 14.5 mid lw upper from bcm.  It is 4 or 5 yrs old, but pretty sure it has a .625 gas block journal.  It wears a thermal scope now, but when it had a razor 1-6 on it, it would shoot 40 gr vmax fiocchi into 5/8-3/4" 5 shot groups at 100.  M855 was usually sub 2" 10 shot and m193 was about like ur results.
View Quote




 
You know, you are actually correct.    I just checked again, and it is .625".  Don't know why I thought .750 for the BCM.  
Link Posted: 3/17/2016 10:11:26 PM EDT
OUT-FRACKIN'-STANDING!
Link Posted: 3/17/2016 10:54:12 PM EDT
Nice work...needs a Noveske Skinny MOE though....
Link Posted: 3/18/2016 12:54:21 AM EDT
Cool. I have a DD upper with the LW barrel that I haven't shot yet. This remind me that I need to take it out next time.
Link Posted: 3/18/2016 1:13:42 AM EDT

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Quoted:


Nice work...needs a Noveske Skinny MOE though....
View Quote




 
I think that Molon has covered the Noveske's pretty well.  Although, I would love to get a Noveske in the collection.




Makes me wonder though, what the most accurate and consistent lightweight barrel is that's out there.
Link Posted: 3/18/2016 2:25:24 AM EDT
Looks like Desert Sportsmans
Link Posted: 3/18/2016 3:01:16 AM EDT
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Quoted:
Looks like Desert Sportsmans
View Quote


Sure is.

Good job OP. If you enjoy testing loads just go ahead and get a good bench setup. You will be happy you did.
Link Posted: 3/18/2016 10:14:08 AM EDT

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Quoted:
Sure is.



Good job OP. If you enjoy testing loads just go ahead and get a good bench setup. You will be happy you did.

View Quote View All Quotes
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Quoted:



Quoted:

Looks like Desert Sportsmans




Sure is.



Good job OP. If you enjoy testing loads just go ahead and get a good bench setup. You will be happy you did.





 
It is desert sportsmans.  




I actually don't do a lot of tests like this, except when I have a reason to do it.  I much prefer to put some steel out at distance and shoot that, or use the short bays for pistols and short range carbine work.  But I have been changing my loads for my Stealth, and going back to basics by working on fundamentals, so it provided an opportunity to test.




Also, I had a perception that the DD barrel had previously shown poor accuracy, so I wanted to confirm that before I pulled the barrel and replaced it. Guess that isn't going to happen now.  
Link Posted: 3/18/2016 10:52:39 AM EDT
Great job, OP!!
Link Posted: 3/18/2016 2:14:46 PM EDT
Awesome post OP
Link Posted: 3/18/2016 2:48:06 PM EDT
Interesting that the DD does better than the BCM.
Link Posted: 3/18/2016 3:29:29 PM EDT



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Quoted:




Interesting that the DD does better than the BCM.
View Quote


I will admit some surprise here.  I had planned on shooting the test, confirming that the barrel was less accurate, and then pull it and replace it.  



Now, I am planning on removing the XTC comp and replacing it with something else.  
Link Posted: 3/18/2016 5:40:48 PM EDT
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Quoted:

Nice work...needs a Noveske Skinny MOE though....

View Quote



Noveske 14.5" Skinny Barrel


...
Link Posted: 3/18/2016 11:31:04 PM EDT
Outstanding job OP!!

Doesn't matter to me, sled or no sled, the consistency between the two rifles is what I enjoyed, and think is most important. As long as all of the controls were the same then that really tells you something.It's just not some pure anecdote.

This took a lot of work, and it's very appreciated!
Link Posted: 3/19/2016 7:29:33 AM EDT
Thanks OP.



I've been thinking of adding a lightweight barrelled rifle to the collection. I think you've helped make my mind up.




It's going to be a Colt 6720 though, due to availability for me.
Link Posted: 3/19/2016 8:17:43 PM EDT
Well guys, I have a bit of a Mea Cupla to do here.  









I was going back over my numbers, and went back to the original targets.  I realized that I had transposed a number when I wrote my notes on the final group of the DD barrel.  Here is the actual target, micrometer on the largest of the 3 groups.  







image by Photographer  Pilot, on Flickr










The largest group isn't 2.5".  It's 1.501".  That means the average group size is 1.251"










Yeah, I am a friggin idiot for mixing that up.  










So that's 1.251", average for 3, 10-shot groups, shot prone, off a bipod on a concrete slab, with a lightweight barrel.  




 



Apparently, I need to be a bit more careful with my numbers, should have included photos of each of the groups.  
Link Posted: 3/19/2016 9:44:41 PM EDT
Very impressive!



















.....
Link Posted: 3/19/2016 9:52:51 PM EDT


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Your measurements are clearly more accurate than my own!







Wish that program was available for Apple computers.  







ETA: I think this may be my new go-to rifle.  Cracks me up, since it was bought new in early 2012, and has less than 500 rounds through it. It's been sitting in the back of the safe, only gets taken out 1 or two times a year.






 
Link Posted: 3/30/2016 6:32:43 PM EDT
Link Posted: 3/30/2016 9:35:40 PM EDT

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Quoted:


Superb!  However in my testing, my 16" middy LW BCM beat my 14.5" Middy LW DD, but not by much



Click here

View Quote
Thanks.



What's interesting to me, is that both BCM's shot similarly when you look at the averages even though yours is a hammer forged, and mine is not.  Additionally your DD also shot similarly throughout the test.  




Mine though shot similarly until I got to my hand loads. At that point, there was a difference.  




So the question is, did I just get a "good" one, or did I just luck onto a specific load that it liked?
Link Posted: 3/31/2016 6:14:13 AM EDT
Link Posted: 3/31/2016 9:56:59 AM EDT
Excellent work.
Link Posted: 4/15/2016 9:41:30 PM EDT
hee,hee,

pencil barrel.

Link Posted: 4/19/2016 8:12:06 PM EDT
Discussion ForumsJump to Quoted PostQuote History
Quoted:

  Your measurements are clearly more accurate than my own!


Wish that program was available for Apple computers.  


ETA: I think this may be my new go-to rifle.  Cracks me up, since it was bought new in early 2012, and has less than 500 rounds through it. It's been sitting in the back of the safe, only gets taken out 1 or two times a year.


 
View Quote View All Quotes
View All Quotes
Discussion ForumsJump to Quoted PostQuote History
Quoted:

  Your measurements are clearly more accurate than my own!


Wish that program was available for Apple computers.  


ETA: I think this may be my new go-to rifle.  Cracks me up, since it was bought new in early 2012, and has less than 500 rounds through it. It's been sitting in the back of the safe, only gets taken out 1 or two times a year.


 


When I occasionally shoot paper I use my work laptop (windows) for on-target, as the apple works for everything else.  Better statistical data from the software than you can easily get measuring

ETA:  And oh yeah, nice shooting!
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