[robertseakykr]

Anybody currently make an aluminum barrel with a non-anodized bore?

[Heaton]

I'm curious as to why you would want something like that?

[robertseakykr]

Just want test it vs. an anodized interior barrel...I'm curious about whether interior smoothness plays much role in shot spread.

[t0ph3r89]

I'm just speculating, but interior smoothness probably doesn't have much affect on shot spread, especially if the barrel is overbored; the ball will hardly touch the barrel's interior. However, anodizing and honing does more than make the inside of the barrel smooth. It makes the surface consistent throughout. If the surface were consistent throughout, and just overall more rough, then I think the only difference would be more strain on the ball (leading to lowered velocity, possibly more breaks, and much more difficulty cleaning after breaks). And this strain would only increase while underboring, making it much less viable if that happens to be one's preference.

[drgonzo]

Flex hone the anno off

[nerve2030]

FYI all the finishing and honing is done before the anodizing. Anodizing is not a coating like paint it is a crystalline structure grown from the surface of the aluminum itself. So when you anodize something your result is only as good as what you start out with.

[robertseakykr]

Anodizing is tough stuff, but is not smooth. Here's a couple of pics I took of some well known barrel interiors:

Barrel A at 100X:


at 200x:




Barrel B at 100x:


and 200x:


Polished aluminum still looks VERY smooth at those magnifications.

[Heaton]

Those images are pretty cool! Here's food for thought: though anodizing may not be as smooth as raw polished aluminum since it changes its crystal structure, its benefit is that it forms a wear resistant hard coat on the surface. Raw aluminum is actually pretty soft, and very vulnerable to granules of debris that can ruin the finish on the inside of the barrel.

I feel as though I want to say that the harder anodized surface would have less friction than a raw aluminum, but I'm just guessing.

[nerdcore]

Microscopic images of stuff creep me out, even something as inane as anodized aluminum.

I think polished brass barrels are popular for this reason.

[t0ph3r89]

Originally Posted by nerdcore

Microscopic images of stuff creep me out, even something as inane as anodized aluminum.

Thought the same thing. I'm unfortunately pretty sensitive to trypophobia triggers.

[Mr. Stealthy]

The Dye stainless steel barrels (and other SS barrels) don't have any anodizing used and there hasn't been any real leap in performance. I would say you probably aren't going to see any gains. Yes the anodizing is a bit rougher, but only on a very microscopic level. The paintball itself is already far rougher in texture than the interior finish on an aluminum barrel. Just my thoughts.

[robertseakykr]

I supect that you're right, any improvements in shot spread will be minor...but I think I'll probably see a pretty dramatic improvement when underboring > 0.004".

Good paint actually has a pretty smooth shell, btw. Here's a Marb and Evil shell at 200x:

[nerdcore]

Originally Posted by t0ph3r89

Thought the same thing. I'm unfortunately pretty sensitive to trypophobia triggers.

So that's actually a phobia? Great, and i thought ADD was my only problem...

[Mr. Stealthy]

I stand corrected, that actually looks pretty smooth. In either case I think you are best off just underboring. I have never noticed a performance difference when using both Titanium and Stainless Steel barrels which were not anodized so I think the effects probably won't be noticeable.

[Jinx18]

Interested in the results. I do believe a smoother bore will lead to less spin on a large underbore possibly helping shot spread leading to no real downside (good shot spread and good efficiency). Currently I think the only option is a stainless barrel which I honestly wouldnt use often due to the weight. Have you considered artificially roughening one barrel to do the testing and see if the hypothesis is right. Much easier then finding a smoother bore.