Precision Rifle Gear Question on RRS Anvil 30 R-lock tension adjustment

[Kiba]

Question for those that have used both the older non r-lock Anvil 30 and the new r-lock version...

I have an older non r-lock version right now. The clamp tension on the rail isn't adjustable, but it can compensate for different rails somewhat as there is a wave spring under the nut. The wave spring compresses and can handle a bit of dimensional variability in the rails and still provide adequate clamp force. It works on all the rails I currently have with no issues.

I keep thinking about picking up one of the newer r-lock versions to either replace mine or for a second tripod setup. The new R-lock Anvil 30 has adjustable tension where you can squeeze the clamp in and then adjust the nut for different rail dimensions. My question is does the new version with adjustable clamp tension still have a wave spring under it so it will accept some rail dimension variability without constantly messing with the adjuster nut, or do you have to manually adjust the clamp nut for proper tension on every rail you put it on? I'm hoping it still has a wave spring in it so I don't have to constantly mess with it.

 

[Vivacious Stallion]

I have one of the original Anvil 30 heads and I recently bought an SC-ARC mount for my ckyepod which I believe is the same mechanism as the updated Anvil head. From what I can tell messing with it, if it does have spring tension based flexibility, it is not to the same degree of the older version.

I was able to get the mount set where it would work on all my arca rails interchangeably, but if I remember it then wouldn't close on a 1913 rail I had on hand to try. The old Anvil will close on everything. I was only going to be running this bipod on arca, so I hadn't investigated it further.

I can mess with it later tonight and let you know or you can try and message RRS on here.

 

[Kiba]

Just looked at the instructions for the SC-ARC clamp as you mentioned and it appears there are 2 belleville washers under the clamp nut to allow some "squish" for the lever camover when closing and also compensate for a bit of rail width variance.

From what I can tell my older gen 2 non r-lock Anvil 30 has 2 for sure and possibly 3 wave washers under the head of the clamp bolt (they certainly don't look like your normal conical belleville washers, but serve a similar function) so it may tolerate a little more rail variance than the newest r-lock version... but that is probably by design as the end user can't adjust the clamp tension on the earlier Anvil 30s.

 

[Kiba]

Picked up an Anvil 30 R-lock, and have to say I have mixed feelings about it.

I like the safety lock on the ARCA lever as well as the R-lock feature. However, I'm disappointed RRS reduced the spring washer stack in the ARCA clamp compared to my earlier non R-lock Anvil, and overall the new one isn't as smooth feeling as my old Gen 2 non R-lock Anvil 30.

My old Anvil 30 closes snugly on 3x genuine RRS rails, 3x Manners rails, and 2x Henderson rails, and is a bit light on closing force but still grabs well on 3x 360 Precision rails. Even though the lever closing is a bit on the light side on the 360 precision rails it holds tight enough the rifle really doesn't move under recoil or if you smack the buttpad hard.

If I adjust the new r-lock Anvil to close snugly on the RRS, Manners, and Henderson rails, it's a very very light close on the 360 precision rails and if you smack the rifle hard on the buttpad it slides in the clamp until an R-lock pin engages. If I snug up the adjuster screw on the ARCA clamp so it closes with moderate force on the 360 precision rails, it's too tight and will not close on on the RRS, Manners, and Henderson rails. The 360 Precision rails need about an extra 3/8-1/2 turn tighter on the clamp nut to have adequate clamping force.

I wish RRS kept the taller spring washer stack from the older non R-lock Anvil 30 in the new R-lock version, then it would accommodate more rail width variation before having to mess with the tension nut. Don't get me wrong, I like the ability to adjust the tension on the R-lock version so it can accommodate more rails-- with the older Anvil 30 and the non-adjustable ARCA clamp if you had an ARCA rail that was too small and the clamp didn't grab it tightly enough you were out of luck. I just wish the new R-lock version had a taller and possibly higher rate spring washer stack so it would maintain good tension on more rails before having to mess with the nut. I'm tempted to make my own splined nut that utilizes a 4x or 6x belleville washer stack with higher rate belleville washers. It would stick out a little bit from the side of the clamp bar, but with 2x or 4x more belleville washers it would likely clamp onto all of my ARCA rails with plenty of tension without needing adjustment of the nut.

Also, as it was received out of the box the clamp lever for the main pivot ball was somewhat gritty feeling and extremely draggy opening and closing even when the lever was in the open position, making it hard to judge how hard it's clamping just by the lever feel. My old Anvil has a clamp lever that swings freely with no drag when open and then has gradually increasing closing force as you close the lever making it easy to judge how much drag was on the head for moving the rifle around just by the feel of the lever. Couldn't do that on the new r-lock Anvil out of the box. However, if I slightly loosened 2 of the screws on the clamp lever arm it moved very smoothly and similar to my older Anvil. I took the new R-lock Anvil clamp lever apart, took some measurements, and lapped 0.003" off each of the thrust washers to eliminate the drag in the open position; the thrust washers were a little thick causing the drag on the lever.

As of now the new Anvil 30 R-lock isn't as smooth as my old Anvil when panning around with light tension on the clamp lever; you can feel a bit of stiction when moving the rifle around, but I'm hoping that will wear in and smooth out with use. My older Anvil is butter smooth but it has quite a bit of use on it.

So far, not ready to part with my old non R-lock Anvil 30 until I get some more time on this new R-lock version...

 

[Vivacious Stallion]

Yikes. I assume that you bought it from a reputable source? I would bet that the ball head will wear in, but my original Anvil was perfect out of the box.

 

[Kiba]

Yikes. I assume that you bought it from a reputable source? I would bet that the ball head will wear in, but my original Anvil was perfect out of the box.

Yep, came from thermal optics plus, and it's from a recent shipment and the latest revision with the retaining screw for the r-lock pin.

Somewhat disappointed I had to take the clamp lever apart and lap and polish the thrust washers right out of the box to free up the lever, but it was an easy fix. I'm hoping the stiction on the pivot ball goes away quickly after some use.

 

[ToddM]

That's unfortunate, it's a hard problem, depending on clamp design some are more flexible with tolerances on the rails and still hold tight. Some picatinny/arca clamps are very picky, I've found the Accutac clamps to be that way. Even across different examples of the same brand picatinny rail I've had to make adjustments to keep them tight, and it's not exactly easy on a lot of designs to try and adjust it while trying to mount to a bipod/tripod etc. The same is true if you use a mix of arca and picatinny, while there's lots of clamps available that you can use on both, you usually have to make big adjustments when you switch between them. So it's flexible, but that flexibility comes with the annoyance of frequent adjustments, granted it's a bit of a "first world problems" annoyance

I find it less annoying with Arca, mostly because you can at least slide it onto the rail and it will hold your rifle somewhat securely while you adjust. With picatinny it's more annoying because since you can't slide it, you have to have the clamp open far enough the rifle can fall out of the mount, so adjusting those tiny clamp screws becomes a bit of case of needing three hands to accomplish. I suppose as long as you refit everything with the same brand and type of rail that holds high tolerances like RRS etc. it probably works great. However, most of us would probably drop $1000+ just on rails to do so, and the reality is most of us end up with some different brands across applications because a single brands designs can't solve. If you want to run picatinny, there's no RRS option, even if you wanted to run their stuff.

The other option of course is to use a non-lever clamp with a tightening knob, but in my experience for heavy items under recoil they often slip, and they also can be annoying to get tightened up quickly when trying to mount stuff. Knobs with levers on them like KNS are great for getting stuff tight, but can be a huge pain to use if you don't have the clearance to "spin" the lever 360 to tighten.

At the end of the day it almost seems like you either deal with having to make some adjustments, or have to make sure you run the same rail system/brand on everything.

 

[vanrichten]

Agreed ToddM, the lever clamp is MUCH more picky about the rail width. The screw clamp is far more tolerant because by design you are tightening as much as you want/need. It's kind of surprising that RRS hasn't come out with a screw knob version of the rloc. They have a lever/screw option for every other one of their heads/clamps. The BTC Pro is a screw knob clamp but doesn't appear to have the rloc like the SC-ARC and their ANVIL 30s.

Personally I hate the screw knob clamp style, even through the lever clamps are far more picky. I've just settled on only putting an RRS rail on anything I want ARCA on, or at the very least a rail that I know for sure follows the RRS standard.

 

[MPHReallyRightStuff]

@Kiba
Grit on new Anvil: we are seeing there is some of that feeling one new due to excess FNC that gets worn in really quick. I am noting it and letting the engineers know though, since I would want to feel blown away immediately when opening the box.

Adjustment: With the original Anvil, with that design you could go on a wider tolerance but it put a mass amount of stress on the rod that goes through the body. The stress would often snap the shaft at the pin hole on the end causing us to replace them often. The new design fixed that with the con of having to have more adjustments. Doesn't help your situation but gives you some insight as to why. Luckily more and more companies are using our drawings for the rails making it less and less of an issue. The next issue shows up when your going to picatinny since there is a wide margin of acceptance there. Which make adjusting necessary again.

 

[Kiba]

@Kiba
Grit on new Anvil: we are seeing there is some of that feeling one new due to excess FNC that gets worn in really quick. I am noting it and letting the engineers know though, since I would want to feel blown away immediately when opening the box.

Adjustment: With the original Anvil, with that design you could go on a wider tolerance but it put a mass amount of stress on the rod that goes through the body. The stress would often snap the shaft at the pin hole on the end causing us to replace them often. The new design fixed that with the con of having to have more adjustments. Doesn't help your situation but gives you some insight as to why. Luckily more and more companies are using our drawings for the rails making it less and less of an issue. The next issue shows up when your going to picatinny since there is a wide margin of acceptance there. Which make adjusting necessary again.

The gritty feel with excess drag on the main clamp lever out of the box was very disappointing, but as soon as I backed off the 2 screws on the upper arm plate and it got smooth I knew what the fix was. I did try opening and closing it about 100 times first to see if it would smooth out and when it didn't that's when I took measurements and lapped and polished the 2x thrust washers to eliminate the drag.

Regarding the new arca latch with the smaller belleville spring stack, I didn't know breaking the shaft at the cross pin hole for the lever on the earlier Anvil was an issue-- but I can see it happening if the user tried to force the lever closed on a wide out of spec arca because the clamp was not user adjustable. Makes sense to reduce the clamp tension a bit to ease the load on the cross pin and rely on the r-lock to prevent slipping under recoil since the end user can now easily adjust the arca clamp tension.