The Lapua Rimfire Performance Center. Projekt CZ 457 – Part II

in Ammo Tests, Authors, Gunsmithing, Matt Kartozian

Updated: August 8, 2023 BY Matt Kartozian

The Lapua Rimfire Performance Center. Projekt CZ 457 – Part II — The LRPC will test your rifle with any of their ammo, but I only tested Center-X.

Read Part 1 HERE: Projekt 457 – Part I

Summary of Part 1: A custom precision rimfire project using a CZ 457, custom barrel, and stock.

With the CZ 457 rifle build complete, and the barrel broken in and ready, it was time to drive over to the Lapua Rimfire Performance Center in Mesa, AZ to find the best ammo. Lapua also has testing facilities in Germany, Finland, Norway, and Ohio. Use this link to find the Lapua Rimfire Performance Center facility closest to you. If you want to use one of the LRPCs in the US you can book an appointment here.

100 Meter test tube at LRPC outside shot — 100 Meter test tube at LRPC. Human error and atmospherics are eliminated during testing.

You can send your rifle to any of the centers for testing, but I opted to go in person because I think watching it all is cool. Your rifle is removed from the stock or chassis and put into a custom-machined bedding block. Your action is bolted into the block with the torque spec appropriate to your rifle model. That block is then clamped into a giant vice that is attached to a large concrete block. The setup is rock solid and the rifle does not move. This ensures repeatability and removes human error in putting pressure on various parts of the rifle and in removing aiming variables from the test process.

Aluminum bedding block for testing actions. — Projekt 457 in the bedding block.

The centers have many bedding blocks for almost any precision 22 rifle. They have blocks to fit CZs, Vudoo and other Rem. 700 footprint actions, Anschutz, Ruger, Feinwerkbau, Kidd Custom, Swindlehurst, Walther and more. Chances are they have one for your rifle. If they don’t, they will sometimes make one.

The rifle is then bore-sighted down the climate-controlled 100-meter test tube which eliminates atmospheric variables like changes in wind, humidity, and temperature. The tube is attached to the test building and the climate control has the added bonus of being very comfortable. I can assure you that doing ammo testing for hours outside in AZ during the summer is awful.

CZ 457 locked in bedding test fixture for lot testing — The bedding block is locked down in a large fixture to keep it from moving.

The tube has a grid of lasers at both 50 meters and 100 meters. There is no target in the tube. The lasers measure the size of your group and display the results on two computer monitors, one for each distance.

Lapua's Rimfire Test Center test tube and computers. — The monitors display your groups at 50 and 100M.

You can choose from most of Lapua’s Rimfire line with Center-X and Midas+ being the most popular in AZ. I’m sure they test more Polar Biathlon in Norway and Finland. I only tested Center-X as it is the lowest price of Lapua’s ammo offerings. I also brought a box of Federal Gold Medal and CCI Standard and a random lot of Center-X I had previously purchased that had shown promise in my testing.

The Lapua 100 meter test tube (inside) — The Tube! Laser grids at 50 and 100M measure your group size.

The Lapua ammo is tested by lots to find what is best for your actual rifle. When I was there they had 9 different lots of Center-X to try. Sometimes more are available, sometimes less. It just depends on the current stock on hand at the test center.

The process usually starts by firing five rounds of a given lot. If the groups look promising another five shots are taken. If the groups are not looking good the lot is pulled and you go on to the next lot. The best lots are set aside for further testing. The process takes several hours but it is well worth it.

Test results from Lapua rimfire center testing — This lot was stopped after 5 rounds as it was not good. Black Circle denotes outside edge to outside edge of the group.

In my case, the testing came down to two lots of Center-X. All testing had been done with the Tandem Kross comp on the barrel. With the final two, I wanted to see what changes attaching a suppressor would make. Typically cans will open groups up, but there is only one way to be sure.

Shockingly, the 2 best lots produced tighter groups with the Surefire Ryder 22S can attached. One of the two lots was slightly better than the other with both the comp and the can attached. That made my choice easy. Sadly the can did not work out in matches. When shooting with the can, it would blow carbon, unburned powder, and other particulate back into the action. The tolerances between the bolt face and the barrel are very tight. About halfway through a match, the bolt would no longer close because of the debris in the action. I can still use the can if I need to shoot a few rounds very quietly, but for matches, I use the Tandem Kross comp.

Testing all the ammo is not free. Lapua charges $50 in the US to do the testing. I have been to the test center twice and both times we shot way more than $50 in ammo. The street price of X-Act is over 50 cents a round and Center-X is about 30 cents. The $50 test fee is a great deal considering the cost of ammo alone, but the data you get is way more valuable. I would not hesitate to pay $100 for a test session.

Test results from Lapua rimfire center testing Center X Lots — Even at 50M different lots of Center-X can produce very different results.

Once you are done testing and you have determined which lot of ammo is best for your rifle, Lapua lets you buy it at a discount. We are over two years into high prices for ammo so Lapua lets you buy direct from the test center. Lapua sells ammo by the case (5000 rounds) and they sell at pre-China Virus prices at just under 24 cents a round when I went to the LRPC.

Test results from Lapua rimfire center testing rimfire ammo — CCI Standard top, Federal Gold Medal Match middle, and my random lot of Center-X bottom.

How much you can buy depends on when you are there and what the current stock is. As I write this purchases are limited to one case every four months. When I was there last September there was a limit of 2 cases. When I was there in January of 2020 I don’t recall any limit.

I had thought the random lot of Center-X I had previously bought shot great in my rifle but I was shocked at just how big a difference the lot can make. The results were staggering. The best lot produced groups less than half the size of the random lot and the Federal GMM and CCI Standard.

The best lot shot a 30-round group with an average of 29.2mm (1.15 inches) at 100m (109.3613 yards) and a Standard Deviation of 10.8. The computers and lasers that measure group size measure from outside edge to outside edge. Most folks in the US tend to measure center to center as it gives you a smaller group size.

At 100m 1 MOA is about 1.14 inches, or 29.1mm. Using the Merca! center to center measurement, my preferred lot of Center-X put 30 rounds into a group smaller than 1 MOA at 109 yards. That is great accuracy for most rifles; it is extraordinary accuracy for a 22LR.

At the start of Part I of Projekt 457 I mentioned that I wanted to see how good a CZ 457 can be, and how it would compare to a Vudoo, the gold standard for precision 22s. The rep at the Lapua Rimfire Performance Center confirmed that the groups shot with Project 457 were equal to the accuracy of the average Vudoo that they test.

They have seen Vudoo rifles that shoot a lot better than the average. One of the most accurate groups shot at the AZ center is from a Vudoo. It shot a 10-round group at 100m in 22.98mm. While the CZ 457 bolt is smooth, it is not the buttered velvet-smooth of a Vudoo bolt. In the end, I was able to slap together a CZ 457 using drop-in parts with comparable accuracy to a Vudoo, but for $1000 less. If money is no object, get the Vudoo. If you want to spend less or have something different, the CZ 457 is an amazing platform, especially when paired with a Craddock Precision Bartlein barrel.

Whatever Rimfire rifle you have, if you want it to be as accurate as possible, mail it in or make a trip to a Lapua Rimfire Performance Center.