Visit the SWFA.com site to check out our current specials. |
Ring Lapping |
Post Reply |
Author | |
catusbill
Optics Apprentice Joined: July/07/2005 Location: United States Status: Offline Points: 161 |
Post Options
Thanks(0)
Posted: March/09/2007 at 22:14 |
I am on my way to do a search for more info, but please read this and make any remarks.
I am lapping my first 30mm rings for a new Leupold scope. Purchase the (competitor)USA 30mm kit, catalog number 879712. Nice kit for $39.00, includes 30mm bar with handle, two alignment bars and jar of 220 grit.
My scope measured 1.182" and my rings before lapping 1.152", with a difference of .030" I lapped the rings for two hours off and on, removing them to inspect to see if machine marks where disappearing. At this time machine lines have faded except for some near the split, a little more on one side than other.
My question is this: Is there an acceptable crush tolerance for scopes rings? .005 - .010 - .015 - .020
Found this link and I bet I will get some feed back from the gurus, CheapTrick, I'm amazed you haven't done the laps.
http://www.opticstalk.com/forum_posts.asp?TID=4823&KW=La pping&PN=0&TPN=1 Edited by catusbill |
|
asphunter
Non-Registered Visitor Larry Root Joined: March/01/2007 Status: Offline Points: 95 |
Post Options
Thanks(0)
|
Sure would have been easier to buy Burris Signature rings.
|
|
catusbill
Optics Apprentice Joined: July/07/2005 Location: United States Status: Offline Points: 161 |
Post Options
Thanks(0)
|
Have them on some of my rifles, 37 rifles and 35 scopes at last count. ASPHUNTER when you retire from the working life your have the time to pit-ell. So, I'm look for things to do besides cleaning the house and doing my wife's laundry. I do clean my area and do my own laundry for sure or I would be out with no rifles.
By the way I finished the lapping last night and precisely positioned the scope with three levels and very thin (.002") double face adhesive. Going out this morning and put a level at 100 yards then mount the rifle in my shooting stand. Bore sighting will consist of leveling the scope's cross-hairs with four foot level at 100 yards.
I guess you would call me a guy with to much free time and a fanatic ! Edited by catusbill |
|
Dale Clifford
Optics Jedi Knight Joined: July/04/2004 Location: United States Status: Offline Points: 5087 |
Post Options
Thanks(0)
|
Wife should lap rings-----shoot more. definitely a crush factor on scope tubes-- never seen one printed- but have crunched a few. What kind of rings? |
|
catusbill
Optics Apprentice Joined: July/07/2005 Location: United States Status: Offline Points: 161 |
Post Options
Thanks(0)
|
I'm using some Leupold Steel 30mm on Double Dove Tail Bases. I did finish them late last night and it turned out very good. Ended up with .008" crush and used 2 mil double sided adhesive tape to line the inside of the rings. It is tricky assembling the scope. But used three small bubble levels, seat scope in lower rings, leveled scope and placed caps on leaving skin on tape. After verification, mounted rifle and checking eye relief, Removed each caps one at a time and removed adhesive backing. Another verification then took it out this morning and placed a four foot level at 100 yards rifle in bench-rest with level. Everything checkout O.K.
|
|
Kickboxer
MODERATOR Moderator Joined: February/13/2008 Status: Offline Points: 23679 |
Post Options
Thanks(0)
|
Ring lapping... Edited by Kickboxer - August/13/2012 at 20:46 |
|
Opinion,untempered by fact,is ignorance.
There are some who do not fear death... for they are more afraid of not really living |
|
excess650
Optics Apprentice Joined: July/31/2012 Location: out there Status: Offline Points: 55 |
Post Options
Thanks(0)
|
uhhhhhh.....pull my finger???
For sure, Burris Signature rings make life simpler. Besides having changeable poly inserts that won't mark the scope (think pillow block bearings regarding alignment) you have the option to tilt the scope. |
|
mil169
Optics Journeyman Joined: February/28/2012 Location: Nebraska Status: Offline Points: 378 |
Post Options
Thanks(0)
|
Did you allow for any air gap between the upper and lower rings for clamping? Was the ring concentric when you measured the 1.152? .030 seems like an awful lot for the manufactor to be under the nominal dimension. My hunch would be that they had planned for a gap of some sort between the upper and lower ring.
Definitely not an "expert" here, just a machinist with a few more scope mounting questions.
|
|
oldfatguy
Optics GrassHopper Joined: August/13/2012 Location: N Alabama Status: Offline Points: 1 |
Post Options
Thanks(0)
|
Virtually all rings are intended to have a gap between the upper and lower halves. TPS is an exception inthat they have a gap on one side only. Some people use feeler gauges to get the gaps even lft/rt.
OFG
|
|
"Ain't no rehab for stupid." C R
|
|
Rancid Coolaid
MODERATOR Joined: January/19/2005 Location: United States Status: Offline Points: 9318 |
Post Options
Thanks(0)
|
I think you ruined your rings.
Lapping is usually not required with good rings (assuming the base or bases are aligned correctly.) Even when lapping, it shouldn't take the kind of effort you indicate. The the rings were seriously bad in the beginning, they may be fine now. If they were within spec before lapping, my guess is that they are way out now. Dammit, I didn't even look at the date. But my comments stand: don't lap rings unless they need lapping, then only take off enough material to allow the tube to move in the lower ring halves without binding. (They aren't binding in the beginning, why the hell are you lapping?)
Edited by Rancid Coolaid - August/14/2012 at 16:38 |
|
Freedom is something you take.
Respect is something you earn. Equality is something you whine about not being given. |
|
SVT_Tactical
MODERATOR Chief Sackscratch Joined: December/17/2009 Location: NorthCackalacky Status: Offline Points: 31233 |
Post Options
Thanks(0)
|
KB, you get 20 lashings for bringing up a post from 2007! |
|
"Most folks are about as happy as they make their minds up to be" - Abraham Lincoln
|
|
Kickboxer
MODERATOR Moderator Joined: February/13/2008 Status: Offline Points: 23679 |
Post Options
Thanks(0)
|
|
|
Opinion,untempered by fact,is ignorance.
There are some who do not fear death... for they are more afraid of not really living |
|
Sparky
Optics Master Extraordinaire Joined: July/15/2007 Location: SD Status: Offline Points: 4569 |
Post Options
Thanks(0)
|
I think he is getting off way too easy with just 20 lashings. |
|
Kickboxer
MODERATOR Moderator Joined: February/13/2008 Status: Offline Points: 23679 |
Post Options
Thanks(0)
|
|
|
Opinion,untempered by fact,is ignorance.
There are some who do not fear death... for they are more afraid of not really living |
|
Post Reply | |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |