Re: Slipping TPS rings
I’ve been following this thread from a personal interest at home and again looked at it this afternoon. My knowledge as I have mentioned before is from the machining side, but the issues, problems and complaints that I have read here on this thread 100% relate back to the machining/technical side, so I thought I would throw some things out that not everybody necessarily thinks of.
First, for the majority of folks on this forum and I’m sure most of the customers in general who are mounting optics to their rifle platform don’t give a rat crap about anything other than having quality components in which they can install and receive satisfactory and above performance from their investment. They didn’t buy a riflescope, rings and or mounts to be required to become an engineer, machinist or a QC Inspector just to get their rig functional. Logical thinking is that the manufacture is the expert and they should have already figured this crap out before I buy, not after, right. Right, sort of.
As I mentioned, my background knowledge is from the machining side, and being my nature, which I believe is good, is that everything I look at is machined wrong. Wrong in that nothing is perfect, whether it is not perfectly round, square, parallel, perpendicular or flat. Nothing is perfect, we try to come as close to perfect as we can or to the extent of the cost involved in making something as close as perfect, but at the end of the day, nothing is perfect, and usually most things are very far from it.
As a point in this discussion, there has never been two rifle receivers ever made in the world which have been identical. Each damn one is different and unfortunately, my recent 6 months of experience with rifle receivers, is that they are the most inaccurate machining on features that relate to optics mounting that I have ever seen in my entire career as a machinist. Every one that I have looked at and measured, which is a lot in the past several months are terrible. How and hell anything stays securely mounted onto a rifle receiver directly from the factory without proper machine truing or epoxy bedding of the bases to the receiver is beyond me.
We have over 30 Remington M700 receivers alone that are available for our internal inspection and not ONE is the same as the other and we even have the engineering prints directly from Remington and only about 3 of them actually meet their engineering prints with regards to true hole position callouts and none of them meet dimension tolerance with respect to the front and rear receiver radius dimensions and heights between the front and rear receiver rings.
The image I included is from our public archive file, which isn’t perfect from my standard, but it does provide a slight insight into what happens when you mount your bases and rings onto a rifle receiver. What it doesn’t show is that regardless of whether you are mounting a One piece or a Two piece base on to your receiver, they WILL BE WRONG!!, to some degree. Hence, the degree and what do me or you consider acceptable error. From most folks, acceptable is mounting your optics without any regard to any of the below illustrations and TA DA, everything appears to work correctly and your scope doesn’t decide to move under recoil, you don’t have any ring marks on your brand new scope, and the point of impact with a bore sight alignment is close, SUCCESS. But, that doesn’t mean its right.
Along comes the average Joe, and mounts everything up and is expecting the TADA again, but no, only crap follows. Well guess what, every component you have just put together has manufacturing tolerances and some have a whole lot more than you wished or thought they did. When you start stacking and compounding all of these components together, guess what, there not going to always work.
As I mentioned in one of my previous post on here, scope rings that leave here are the most precision scope rings I have ever seen. I have worked at another optics company in Oregon in the years past, and I can tell you, these are light years beyond those.
The truly aquilles heel that TPS has, in my personal opinion, is it’s trying to build scope rings to meet Boeing standards knowing that are going to be mounted on a galvanized pipe intended to hang cyclone fencing on, and please no offense intended on comparing your optics to a cyclone fence. The ring bores on the rings made here have a maximum tolerance of .0002 per inch cylindrical roundness and a .0005 bore diameter. We have over 100 scopes in QC for size comparisons and they deviate as much as .010 from one to another. Leupold & Stevens is by far the most accurate from any we have in QC, but they have as much as .0015 variances between models. The average deviation from brand to brand is .005 in diameter. Welcome to my analogy of scopes and cyclone fences. Nothing is perfect and usually is far less than perfect.
So, you ask, why the $%#&* did my ABC rings work before and now I buy this TPS brand and my scopes slip. Well, because TPS, in the infinite wisdom decided to make a scope rings extremely accurate in the bore size. Well, the question bears asking, and I’ve asked it in my first week of working at TPS. Why the $%#&* don’t you make them like everybody else. Response, “Because there is a large percentage of shooters who know the difference between right and wrong. And we will not give in to providing an inferior product design just so that a small percentage of people will not have problems in mounting their rings in the improper manner at the expense of the many who know the difference.” For right or wrong, I think with over 250,000 pairs of rings in the world today from TPS and with such a small percentage of issues which as has been mentioned here, isn’t too bad. Of course, from my view there all bad.
I’ve worked at an optics manufacture in the past and have personally watched the extreme precision which goes into the assembly of a rifle scope. I can personally be a little critical about some of the tolerances which eventually go into the final assembly, however when it comes to utilizing lasers and extremely precision and expensive optical alignment machines to align all of the lenses close to perfect, it is impressive. However, the same story played out their as it does here, they spend all of this time and expense in aligning the lenses to a tenth degree and attempting to provide a quality end product out the door only to have the product slapped into a set of poorly aligned rings and bases and destroy everything that had just spent all that time aligning. A very sad and unfortunate process but the norm.
The most notable difference between TPS brand rings from everyone else is the ring bore size and its cylindrical roundness. Take a Mark 69
tactical ring and compared the ring bore. The ring bore runs .005 oversize from the scope tube, as does many brands of rings, and I think we have them all for internal review. When you screw down the ring cap down on a typical scope ring base you are “Crushing” the optics tube to mechanically prevent the scope from moving, hence the “Ring Marks” you typically find on previously mounted optics. If you’re scope ring diameter is .005 oversize from the optics tube, you are only contacting about 5% of the tube at initial ring cap assembly. The only way to obtain more contact on the scope tube is to increase the torque on the screws to force the scope tube into compliance.
, thereby actually deforming the tube mechanically to prevent slippage, as it done millions of times a year. Sure, it works, but to what price to the highly precision aligned optics inside.
Now take a scope ring which is typically within .0002 to .0005 diameter of the scope tube that is being mounted. Now you have close to 98% contact, enough contact that allows the scope to be held in position by using “Friction” between the scope ring and the optics tube, not by “Crushing” the tube to conform to an “egg shaped” ring bore. Further, by having extremely close diameter fit between the ring and the optics tube, even with excessive pressure from torqing the ring cap down, the optics tube is better protected from crushing because the entire circumference of the scope tube is supported due to the extremely close tolerance bore, rather than an oversize ring bore, hereby causing the scope tube to be deformed to fit the ring bores.
Last but not least, if your scope tube has been marred or is slipping wiht TPS rings, it’s because the rings are out of alignment so far that it is damaging the scope tube to conform to the mis-alignment or your percentage of contact has decreased due to the angularity between the scope tube and the ring bores or both in any or all of the 3 axis that are involved in alignment of your sets of scope rings, PERIOD. (No sugar on top)
Notice: EVERY SINGLE RIFLE IN THE WORLD HAS MISALIGNED RINGS. The questions is, is it within a close enough tolerance not to damage the scope tube and thereby effect the function, alignment and the end performance of the optics being mounted.
NOTICE TWO: Using two alignment bars with a pointed end on each end to align the two points up between the two rings doesn’t tell you squat, matter of fact, it’s less than squat. The rings could be 15 degrees off and the points could still align.
Looks like I wrote a novel again, things have been running exceptional smooth today, so had time to kill, as long as I don’t get caught killing time.
More to come, if time and job allows……
