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Discussion Starter · #1 ·
Sent my 16" light .308 barrel to ADCO to get cut down and fluted. They told me they can't flute it because it's a tapered barrel, unless they contour it so that it's straight. So...is it a bad idea to make the contour flat (on an already light barrel) and then flute it? Is this compromising the barrel's strength too much?
I've seen a lot of threads on fluting a heavy barrel but none on a light. Just want to make sure I don't do something stupid.
Thanks.
 

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These are just my thoughts and by no means the definitive answer. I think it's a bad idea to trim the contour. I'm assuming the tapered barrel is thicker towards the chamber? That is where material is needed the most. Trimming it down to get a straight contour will likely affect your accuracy and barrel harmonics; by how much? I do not know. The S&W M&P 10 has a tapered 18" barrel, and its accuracy is well documented in various online reviews. Given the -M's record for accuracy, I would not do anything to that barrel to make it even less accurate.
 

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Discussion Starter · #3 ·
Correct--the barrel is thicker toward the chamber, but when you look at it, it's a very very slight taper (I didn't even think it was tapered until they told me it was). This makes me think it might not be that big of a deal to make it totally straight, but I'm not an expert...
 

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Yeah, they do good work. However, the benefits of fluting a light barrel are almost entirely cosmetic.
 

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Yeah, they do good work. However, the benefits of fluting a light barrel are almost entirely cosmetic.
Depends on the context. It does remove material, thus decreasing weight. It also increase surface area, thus aid cooling... theoretically. Real question is by how much and does it make enough of a difference to be considered a real functional enhancement. Definitely not done with cosmetics in mind here as the fluted portion is hidden from sight.
 

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Discussion Starter · #11 · (Edited)
Went to zero at 200 yds today. Wind was a pain in the ass (gusty). However, there were a few groups I managed to send off while the wind was low and my natural point of aim was solid.

Bottom line: 3-inch groups at 200 yds = approx 1.5 MOA out of this thing. I'm pretty pumped!!!

Need to go back when the wind is dead calm just to really nail down my zero, but it's like 95% there. Aircraft Wood Vehicle Monoplane Aviation Wood Wall Insect Road surface Tints and shades

One caveat I will say (not to insult anyone), but you REALLY have to have a good setup so you can get a SOLID natural point of aim. I thought my trigger squeeze was good enough but when I started out I was getting 8-inch groups at 100 yds, swearing I saw the crosshairs on the target as the bullet went off. But then I really focused on closing my eyes, exhaling, and opening them to see where the crosshairs were. If they didn't naturally fall right on the bullseye, I had to adjust my body (not the gun) until it was right on. Unless you do make sure you do that, those rounds are gonna fly. Most of you probably know all that but I thought I'd throw it out there.
 

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Discussion Starter · #12 ·
We are looking forward to a before and after accuracy report. It looks good.
See my last post--much better than I was expecting.

Also of note, I now have to keep it on the highest gas setting to keep it cycling properly (now that the barrel is so much shorter). Doesn't bother me though--as long as she works
 

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With regards to the POA.

I've been paying a lot more attention to how I shoot my M the last couple of sessions. Solid bipod mount sand bag under the stock and made sure I wasn't forcing the rifle in a direction it didn't want to go. Lots of positive pressure on the stock, into my shoulder and at the cheek weld. Earlier sessions were 4-6" at 100. Now I'm consistently at 2-2.5".
I'm not a competition shooter but my comparison between the M and my stock bolt gun (yes they're two different platforms so they will "shoot" differently) with the same ammo and conditions left me really disappointed in the M. Until RA can tell me my rifle is in spec, and there being a known problem with certain rifles, I'm hesitant to chalk it up to just my ability.

If RA comes back and says the rifle's good...... Shit. If there's a problem, I'd hope they fix it and the rifle shoots consistently.
 

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That does not look safe. I linked it to the engineer. I will talk to him about it.
If you're talking about ADCO's fluting, the company has a good reputation and I'm sure their safety minimums for barrel wall thickness are well-considered. I have several ADCO-fluted HBARs -- I just can't imagine any significant weight savings from fluting a light barrel. (But maybe the -M LBAR is a heavier profile than the -L in 7.62x39.)
 

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So it could double as a grenade?:D
 
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