7mm SAW, baby's first wildcat. (Long post)

The fuck is 7mm SAW?

Essentially a 7mm SLR would really be the closest thing that comes to mind. It was developed, and used in last year’s PRS finale by Clayton of West Texas Ordnance to drive 7mm pills faster than vanilla 7-08 without the hassles of an Ackley improved case design such as possible feed issues, fire-forming and neck turning. It uses a 308 case and is necked down while changing the shoulder angle with one pass through the sizing die.

WTO recommends the Lapua 308 “palma” brass specifically for the consistency of the small primers and the increased pressures the case can handle.

The case itself holds 55.6gr H2O to overflow and uses powders around the Varget to 4350 burn speed to push the 162gr ELD-M up to high 2800s to low 2900s and the 180gr bullets to around 2700ish, depending on how hard you want to push it.

Pic 308 palma on the left 7 Saw on the right

Ya, but Why?

I really wanted to try a wildcat caliber for some unknown reason but didn’t really want a barrel burner like most if not all the 6mm wildcats out there suitable for PRS-style matches.

The 7 SAW not only has a bit more barrel life than the popular 6.5 offerings (Lapua, 260 Rem and Creedmoor) but as far as wind and drop, it falls right in-between the 6.5s and 6s performance-wise. A bit better than the 6.5s but just a bit worse than the 6s for drop and wind.

The only tradeoff is a tiny, but still very manageable bit more recoil than the 6.5s.

The Rifle Pic Back from WTO around New Years, Krieger 1:8.5 twist Heavy Varmint barrel finished at 24” (Stiller Tac 30, KRG, X-Ray, Timney Calvin Elite trigger, Recce 7 Silencer, Nightforce ATACR 5-25 Mil-C)

Reloading

For reloading WTO offers a set of Custom Redding dies with a seating micrometer or a set of Whidden bushing reloading dies. All it takes is one pass through the sizing die and the brass is done.

Measuring on the .375 datum line with a Hornady headspace gauge, my virgin brass chambered at 1.620, fired cased came out to 1.623.

There are two available chambers for 7 SAW, a type 1 with a shorter .045” freebore and a type 2 with a longer .150” freebore. If you mostly use the magpul or standard ACIS mags the type one is what you’ll want. But if you already have several 3.000” internal OAL mags like the accurate mags without the binder plate type 2 is the way to go as it allows you to seat the bullet out further on the bearing surface and gives you more room for powder.

For breaking things in a bit and get the barrel to speed up some, my first 200 rounds were virgin cases with a mild charge of 39gr Varget and a CCI 400 SRP. Velocity was 2680, SD of 3 and ES of 10 over 10 shots. Most groups were right around .4” to .5” at 100.

Load development with some H4350, 162gr ELD-Ms and the same CCI 400s, Results Pic had two nice nodes one at 46.3gr going 2810, that I went with, and a little slower one at 45.5gr going 2765. Though according to WTO it can be loaded with H4350 up to 47.4 grains but it does start to compress around 46gr. While not up to 2900fps the barrel hasn’t worn in much and should speed up a bit more with a few hundred more rounds down the pipe.

After the next match or two coming up are out of the way, I plan to try out some more Varget as well. It seemed to take up less case capacity which might let me push the velocity a bit higher. Its also a lot easier to find more of. Ideally I’d be happier with anything above 2850 for the 162s but 2800 is fine for now.

Other take aways

Overall pretty happy with the cartridge so far, I think it has a lot of potential and its been a lot of fun reloading for. It’s a fun wildcat that doesn’t take a ton of extra work to enjoy.

I’ve learned a lot I didn’t know about reloading going through this project for sure. Clayton and the WTO crew are more than awesome. They answered all my reloading questions (however dumb, and frequent, they might have been) super fast and were extremely friendly. Not to mention the excellent quality of their work. They even called me up to let me know that my recoil lug wasn’t exactly right and fixed it with one of their recoil lugs without charging me extra for it.

Overall I would highly recommend them, they have a few other wildcat designs on the website as well as a switch lug design which looks very interesting too.