What height scope rings on MPA
- Thread starter Kubitza123
- Start date
50mm objective doesn't mean that the scope's diameter is exactly 50mm. Look at what the scope's actual objective diameter is from their specs sheet / manual. But in general with that rail on the CZ, generally .9-1" rings would work.
There are many methods to determine appropriate ring height, but the one that has worked best for me is to take equal stacks of pennies or nickels and place them on the rail/base. Place your scope on the stacks and adjust the stacks until you have the desired objective and power ring clearance. Use a caliper to measure the stack and add that to half the tube diameter (remember to use the same units of measure).
Keep in mind you need to allow enough clearance for the addition of a sunshade and or objective cover, especially if you use anything other than than a 0 moa rail.
I have a CZ 457 Varmint with a BScar 25 moa pic rail and an Athlon Ares BTR 4-27x50 (30 mm tube) in Seekins rings. Using the above method, I found that I could get by with med (no objective cover) or med/high rings; however, to add a sunshade I needed to use high (.97) rings.
Not sure if this is what you were looking for, but hope it helps.
Keep in mind you need to allow enough clearance for the addition of a sunshade and or objective cover, especially if you use anything other than than a 0 moa rail.
I have a CZ 457 Varmint with a BScar 25 moa pic rail and an Athlon Ares BTR 4-27x50 (30 mm tube) in Seekins rings. Using the above method, I found that I could get by with med (no objective cover) or med/high rings; however, to add a sunshade I needed to use high (.97) rings.
Not sure if this is what you were looking for, but hope it helps.
I have seen the penny method, but can't do it till I receive the rifle (30 MOA scope rail) and scope (I will be adding scope caps). Was trying to order mount or rings prior to getting it in.
I am often in your shoes, not knowing the actual diameter of the lens objective barrel.
My technique is to take the glass diameter and add 9mm to estimate the actual objective barrel diameter. In your case, 50+9=59mm.
Then subtract the tube diameter (I’m going with 30mm tube). 59-30=29mm
This gives you the scope “flare” on each side of the tube. To get just one side (the side hanging down), divide by two. 29/2=14.5mm
So, given a straight line from the mounting surface, in order not to hit that surface you would need a ring that is at least 14.5mm tall (ignoring the bits that grab the rail, the ring is measured from the bit that sits on the rail to the bottom of where the scope would set).
If you have a barrel that slopes down from the receiver, then you have more space to work with. With your MPA, the barrel is quite a ways beneath the top of your picatinny rail. Let’s pretend it’s 8mm lower. Then, take the 14.5mm above and subtract 8mm to get your minimum ring height (6.5mm).
Some manufacturers measure their rings from the part that sits on the rail to the center of the imaginary scope tube. In this case, take that measurement and subtract half of the tube diameter. Or go to Midwayusa.com and read their specs, as they’ve already done that.
Make sense?
If it doesn’t, it really helps to draw it out.
My technique is to take the glass diameter and add 9mm to estimate the actual objective barrel diameter. In your case, 50+9=59mm.
Then subtract the tube diameter (I’m going with 30mm tube). 59-30=29mm
This gives you the scope “flare” on each side of the tube. To get just one side (the side hanging down), divide by two. 29/2=14.5mm
So, given a straight line from the mounting surface, in order not to hit that surface you would need a ring that is at least 14.5mm tall (ignoring the bits that grab the rail, the ring is measured from the bit that sits on the rail to the bottom of where the scope would set).
If you have a barrel that slopes down from the receiver, then you have more space to work with. With your MPA, the barrel is quite a ways beneath the top of your picatinny rail. Let’s pretend it’s 8mm lower. Then, take the 14.5mm above and subtract 8mm to get your minimum ring height (6.5mm).
Some manufacturers measure their rings from the part that sits on the rail to the center of the imaginary scope tube. In this case, take that measurement and subtract half of the tube diameter. Or go to Midwayusa.com and read their specs, as they’ve already done that.
Make sense?
If it doesn’t, it really helps to draw it out.
Last edited:
I have CZ 457 with 15MOA Area 419 rail , with Athlon Ares BTR 4.5-27X50mm using 30mm tube by .97 Vortex rings. The barrel is a Lilja .920 dis SS non tapered , this allows about 3/8” + or - under the 50mm bell which is actually bigger then that when you consider the OD of the bell.
Last edited:
Don't see much info on these MPA CZ complete rifle builds. Any feedback from you owners yet??? Especially wondering about the house barrel. Looks like a nice package.
just ordered mine last week, went with 18in barrel, just have to wait now. I'll post as soon as I get it
