By Pete Petros-Lead Reloading Technician, Sinclair International

After hearing about great results that shooters have been having with the original .284 Winchester I decided to re-barrel and chamber my factory Savage F-Class 6.5mm X .284 after 1200 rounds of ¼ MOA accuracy had opened up a bit. I contacted Dave Kiff from Pacific Tool and Die to have a reamer made based on the Norma specifications for the .284 cartridge necked up to 7mm with a tight .313” neck. Mark Penrod of Penrod Precision in North Manchester did the art work on the rifle. I had him use my new reamer to chamber a 31” Bartlein 1-9” twist 5R barrel that tapers from 1.25” to .900”. He blue printed and bedded my action in the modified factory stock and tweaked the Rifle Basix SAV-2 Trigger. I received the new upgraded rifle two weeks before I left for the 2009 F-Class Nationals at Camp Butner, North Carolina. I had to squeeze break in time and load development in a short time period. Fortunately, I had all of my brass prepped and ready to go once I had the rifle home.

I took the Lapua brass and expanded it from 6.5mm to 7mm with a Sinclair Expander die and mandrel. Once that was complete I turned the necks down with a Sinclair NT-4000 Neck turning tool from .0145” to .0135” to allow .002” clearance from the chamber. One step I took and was glad I did was to turn all of this brass under power with the use of a Sinclair Power Center and Case Driver/Holder. This made the job much easier without losing accuracy. Using a Redding Type-S Full Length Die with a .309” bushing I assured a perfect .002” of neck tension. The bullets I chose to build my load on was the Berger 7mm 180 Grain VLD, seating them into the case with a Redding Competition micrometer seating die. This bullet has proved itself with others shooting this cartridge. This high BC bullet is hard to beat at long ranges.

In load development I began working with Hodgdon H4831 SC powder with CCI BR2 primers. Once again this had proved to be a great powder with other shooters and I already had a good amount left over from loading for the factory rifle. After break-in and a few trips to the range I settled on a load, and a seating depth of .020” of bullet jump to go to take to the nationals. I was blown away by the load I had chosen. I found it to chronograph at 2820 FPS with an ES of 6 FPS! Additionally, it was shooting ¾” groups at 300 yds! What was best about this was that I had stumbled on this load early in development and could work on other areas before the competition.

Almost a year has passed and the rifle is shooting better than when it was new. With around 900 rounds through the same barrel I have not seen the slightest effect on the throat or rest of the barrel that would show signs of burning out. One thing that I had found after the barrel had broken in is that I noted velocity increase to 2920 FPS. However, the group size remained tight and ES over the chronograph remained very low without any noted pressure signs. At the same time I gained a full MOA from my 300 yard zero to 600 yards. Can’t complain about that!

I have found the .284 Winchester to be a more superior cartridge to the 6.5mm X .284 in my experience in 600 and 100 yard F-Class Competition. Besides the longer barrel life it has other advantages. The ability to shoot a heavier bullet with a higher BC excels in wind. I have found that this cartridge has proved to be more consistent across the chronograph, and retains its accuracy. It definitely has not been as touchy as the 6.5mm. Who would have thought that going up .020” in bullet diameter would have made such a difference. There is a slight recoil gain over the 6.5mm but nothing to flinch at.

So if you are looking for a great long range cartridge, check out the .284 Winchester. Sometimes the original is best as in this case, it sure is my opinion! You can use either factory Winchester brass in .284 Win. or any 6.5mm X .284 brass and neck up in a simple process. I highly recommend that Lapua brass is used. I have 8 firings out of the original brass, anneal every three firings, and it still works wonders! When working up the load be cautious of on-line loads, use official loading manual data and work your way up in powder volume. Many .284 shooters such as myself have used Hodgdon 4831 SC with great results but I have also heard of good results with H4350, Vihtavouri 560, and Reloader 17. Give it a shot, you will not be disappointed!
Good Shooting!

Contacts
Pacific Tool and Gauge- 541-826-5808
Penrod Precision- Mark Penrod- 260-982-8385

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