Strange rollers

**cz759** · 04-21-2010, 12:27 AM

I bought these rollers from RTG at a gun show sometime ago, planning for the future. Well I got my new bolt head and locking piece the other day . I decided it was time to put everything together to get a better bolt gap.
got everythging assembled, checked the gap..WTF...bolt gap went down. Pulled the new LP, resintalled the old one....same same. After swaping the parts around a couple of more times and getting the same reading. I finally took the rollers out and measured them. The rollers measured at
7.98mm, another set measured 7.96mm. Excuse my ignorance but I thought the single stripe rollers were 8.02mm.
Got any ideas what is going on here??????

**Jsquared** · 04-21-2010, 12:32 AM

I believe the single stripe rollers are -2, the "+" being -4

Edit: actually Im not so sure now, can't find a definitive source. RTG has those marked as +2, but has "+" for -4, and the double line as well as the double circle mark for +4.

**HKaltwasser** · 04-21-2010, 12:37 PM

Those are +2 rollers. I pulled mine out to double check,yep I gained gap off of these. I don't know why it would drop gap unless you have +4 rollers already in there. Weird why they're measured at 7.98 though but marked for 8.02.

**kmagnuss** · 04-21-2010, 12:59 PM

I thought the single stripes were -2 rollers also.

**jfowl31** · 04-21-2010, 01:08 PM

+2's

http://www.militaryfirearm.com/Forum...52&postcount=9

You probably already have +4's in your rifle. Are they ACTUALLY measuring 7.98 mm? or is that an assumption based on what the originals?

**SteelCore** · 04-21-2010, 02:54 PM

Sure look like +2s...are they used?

**cz759** · 04-21-2010, 05:01 PM

OK. No, the rollers are brand new. Digital mic. to 7.98, old rollers mic. to 8.00
that is where the confusion exists. Possibly they were mis-marked. and another set without stripes that should be 8.00 mic. to 7.96. I checked the sizes with two digital mics, and calipers same reading

**jfowl31** · 04-21-2010, 05:11 PM

sounds like the ones with no markings are actually 8.00, the 1 stripe are 8.02, and the old ones are 8.04 to me.

- sized rollers are not very common really. I would bet its just either the mics needing to be calibrated, or something like that.

You could TRY to get some more +4's or even ask for an exchange, but my gut feeling is that you had +4's to begin with.

**Smokehouse69** · 04-21-2010, 07:55 PM

You must have a better set of digital calipers than I do. My Harbor Freight calipers aren't accurate enough to measure that close. Heck if I breathe on them they change .02 mm.