Micro Grooves (Marlin Rifling) in Barrel

[Zulu__Dawn]

Hey guys,

Me again.  I was looking at my rifle that I just got.  Giving it a full inspection before I take it out Saturday....still waiting to take is out and give it a workout.  I had a question about my barrel.

It looks polished?  It is super shiny when I put a light through it and look down the barrel from the breech.  I notice that it looks like it has little to no rifling...I can see very small...I mean like almost not there lines running in a twist down the barrel.  But these are small...super small...so faint.

Just wondered from some of you experts...are these Microgrooves from the Marlin type rifling?  Is it supposed to look like this?  I mean if the light doesn't hit the landings just right the barrel almost looks like a smooth bore.

I this okay?  IF this is okay...Is this the most common type of rifling in air guns???

Zulu

[Roadworthy]

I haven't looked at your barrel, but airgun rifling is not as pronounced as powder gun rifling.  A deep rifling would create too much drag and slow the pellet too much.  The air against the skirt forces contact with what rifling is there causing it to spin.

[Rocker1]

What kind of airgun is it??  David

[BigTinBoat]

What kind of airgun is it??  David

I would think this one likely.....

As mentioned I purchased the Stoeger ATAC Suppression rifle .22, for plinking and hunting.

can't help though as I have not seen any Stoeger barrels

[Zulu__Dawn]

Correct, it is a Stoeger ATAC.  Made in China/Taiwan...

This is the 1st Stoeger I have seen, and I have not seen air rifle bores in the past.  This is the 1st one I have owned, so I have nothing to compare it too.

I have another rifle in the mail right now.  The Benjamin Titan GP that was on sale for 99.99 -11% last Monday.  It will be here Tuesday...

I know the barrel is finished and the right dimension because I have put 2 pellets through it already and the pellets fit nicely in the breech...so as I said dimensionally it is correct.  I was just wondering...does this rifle ship without rifling???  That would really be, not cool, if I lose accuracy because of this.

I do know that Microgrooves can be as fine as .0015 on a mill, which is almost nothing to the eye.  These marks in my barrel almost look like faint scratches put in with a Honing Stone.

Zulu

[bgmcgee]

I say run some patches with goo gone down it, get it clean and shoot the heck out of it. If it doesn't meet expectations return under warranty.  No worries.

[45Bravo]

Most guns have 6 lands and grooves, for rifling.
Some old springfields and others used 2 grooves.
Some guns have 4, some 6 and some 8.

It just depends on who made the barrels.

The marlin micro grove .22 barrels have 16.

The micro grove is not so much as how deep it is, but how wide they are.

As mentioned, the air gun rifling is not very deep, and is actually sometimes called button rifling.

We only have a limited amount of pressure to get a projectile down the barrel, unlike a powder burner that is using an expanding chemical reaction.

On the FX guns, they use what is called a "smooth twist" barrel, it has no rifling for most of the length, then starts to spin the pellet toward the end of the barrel.

Very novel idea, and is very accurate it seems.

[45Bravo]

. Shoot it and see, who cares what it looks like as long as the groups are outstanding.
John

Ain't that the truth!!!

[Zulu__Dawn]

Yeah...you guys are right.

Forest through the trees right???  Who cares what it looks like if I am shooting the behind out of gnats at 50 yards.

I'll find out tomorrow...taking it to the Marine Corp shooting range tomorrow at Camp Pendleton.  I'll let you all know how it goes.

Zulu

[Privateer]

Wasn't a micro type groove proven years ago when they still fired round balls?
Seems I saw something about that in From Trigger to Muzzle?