June 29th, 2015

Applied Ballistics Tests 50+ Types of .22 LR Rimfire Ammo

.22 LR Rimfire Ammunition testing Bryan Litz Applied Ballistics Eley
Photo shows Bryan Litz (on right) and tester Mitchell Fitzpatrick. Bryan said: “Only 2,445 rounds to go! We’re testing over 50 ammo types in five different twist barrels… science can be exhausting!”

Do you know the actual BC (Ballistic Coefficient) of your rimfire ammunition? Well Applied Ballisitics will soon have answers for you. Bryan Litz and his team of testers have been working on a Herculean project. They’ve been testing over fifty types of .22 LR ammo, using five different twist-rate barrels.

.22 LR Rimfire Ammunition testing Bryan Litz Applied Ballistics Eley

.22 LR Rimfire Ammunition testingBryan tells us: “We’re testing many types of .22 rimfire ammo for the next edition of the Ballistic Performance of Rifle Bullets book. We’re using a pair of Oehler chronographs to measure velocity at the muzzle (MV) and velocity at 100 yards.” With these numbers (average and SD) Bryan can calculate G1 BCs for all the 50+ types of rimfire ammo. What’s more, because every sample is shot through five different barrels (each with a different twist rate) Bryan can also determine how velocity is affected by twist rate.

The tests are primarily to determine velocities for BC calculations — this is not an accuracy test. Bryan explains: “Our tests are not really looking at accuracy, mainly because that’s so subjective to different rifles. Our testing is primarily focused on measuring the BC of rimfire rounds from different twist-rate barrels. The MVs and BCs from the different twist test barrels will be published in the upcoming second edition of Ballistic Performance of Rifle Bullets.

Will the rimfire data be added to the popular Ballistics Apps? That might happen in the future, says Bryan, but he’s not sure when: “We haven’t determined to add the .22 rimfire data to the ballistics Apps, but it’s a possibility.”

Bringing Science to the Rimfire World
Bryan’s goal with this project is to increase the rimfire knowledge base: “We hope to give the world of .22 LR rimfire a good dose of science. How is the BC of .22 rimfire ammo affected by barrel twist? Do subsonic rounds have more consistent BCs than supersonic or transonic rounds? What brands have the highest BCs? What brands have the most consistent MVs?”

.22 LR Rimfire Ammunition testing Bryan Litz Applied Ballistics Eley
Data from two Oehler chronographs is recorded in a computer. Ammo samples were tested in five (5) different barrels (of varying twist rates). Give credit to Dane Hobbs who supplied a test rifle, multiple barrels, and most of the ammo types for the test.

.22 LR at 300 Yards?
Bryan also conducted some longer range rimfire tests. His surprising findings might appear in the next volume of Modern Advancements in Long Range Shooting. Bryan notes: “While .22 rimfire isn’t typically considered ‘long range’, we were able to consistently hit a two-MOA steel target at 300 yards with the trajectory predicted by AB software and the measured BC of some standard .22 LR rimfire ammo. The info we’re generating may make it possible to push the range of target engagement for a round that’s not seen much advancement in many decades.”

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