Loading Precision .338 with Triebel Dies

It’s incredibly rewarding to build a rifle, load the ammo for it, and shoot it to measure the results. I decided to take out the .338 Lapua Freedom Rifle and do some load development with it. 


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About the .338 Lapua Build

My Cerakote Freedom Rifle masterpiece is centered around a BAT HR long action in an MDT ESS chassis. I built this with an abundance of Triebel tools and reamers on the Precision Matthews TL-1660.

To see the full build with Blackhound optic, watch the full video! 

Load Development

When first sighting in, I managed a three-shot .695” group with some windage dispersion.

This was with 94 grains of Hodgdon Retumbo, Federal 215 Magnum primers, unfired Lapua brass and Berger’s 250 grain hybrid OTM tactical bullets.

Cartridge overall length measured 3.676.” This was a good start, but I decided to jump to the Lapua 300 grain Scenar bullets and Berger 300 grain hybrid OTM tactical bullets.

I loaded three Scenars over 92 grains of Retumbo and fired a 0.586” group at 100 yards with the CKYE-POD and rear bag. Standard deviation was 5.2 fps and extreme spread was 12.7 fps. From there, I loaded ten of the same. The first five shots tore a tight 0.509”/0.486 MOA hole at 100 yards.

While I had reduced the charge from my very first sight-in, I kept the seating depth the same as I did with the Berger 250 grain hybrid OTM tactical bullets. I did have some difficulty chambering the rounds, so I opted to adjust seating depth. With these results, I was eager to see what I could do with load development on the concrete bench as well. This is only the very beginning of my load development process.

Reloading Equipment and Process

I loaded this ammunition on the Redding T-7 press with Creedmoor Sports adaptive press head using the Triebel .338 full length sizer and Triebel .338 Benchrest seater.

These 1 ¼” dies worked well with the quick change system of the adaptive press head. Loading for .338 Lapua on this press was a little tight, but there was still plenty of room for the bullet. 

I used the Primal Rights competition primer seater to seat the primers.

Powder passed through the RCBS MatchMaster and made it into each case via the AREA 419 funnel kit with .338 adapter. (Be sure to take a look at the RCBS app to set up the press.) To check each loaded round, I passed it through the Lyman ammo checker and measured the shoulder bump on the Hornady headspace comparator. 


It’s been fun to get back to working with the powerful .338 Lapua and quality 300 grain bullets. Let me know what you’re loading in your .338 Lapua! 

Get the Gear

Triebel .338 Sizing Die at Creedmoor Sports 

Triebel .338 Seating Die at Creedmoor Sports 

Creedmoor Sports Redding T-7 Adaptive Press Head

Creedmoor Sports Redding T-7 Adaptive Press

Berger .338 250 Grain Hybrid OTM Tactical Bullets 

Berger .338 300 Grain Hybrid OTM Tactical Bullets at Creedmoor Sports

Lapua .338 300 Grain HPBT Scenar Bullets at Midsouth Shooters Supply

Hodgdon Retumbo at Midsouth Shooters Supply

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Gavin Gear

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