Sierra .308 195 gr. Tipped MatchKing (TMK) load development: 308 Winchester and VARGET
In Sierra .308 195 gr. Tipped MatchKing (TMK) REVIEW and load development: 308 Winchester and IMR 4064, we had a first look at the 195 gr. Tipped MatchKing (TMK) in the 308 Winchester. The results were quite impressive, the final load offered significant advantages at longer distances. In this post, I’ll take a look at how the 195 TMK works with Varget, another popular powder for the 308 Winchester with heavy bullets. If you haven’t read my initial post on the 195 TMK in 308, please do, it provides a framework for the discussion in this post.
To recap, the 195 TMK is advertised with a G1 ballistic coefficient of .610 above velocities of 2,000 feet/second (the ubiquitous 175 SMK has a G1BC of .496 between 1,800-2,800 feet/second), Sierra recommends the 195 TMK for barrel twist rates of 1:10″ or faster.
Once again, the test gun is a custom built Remington 700 chambered with a Manson 308 Match reamer. Referred to as “OD 308” in my range book and notes, this rifle is one of my favorite shooters. It was built with the following parts from Brownells:
- Remington 700 short action receiver
- Shilen #7 Select Match barrel, 1:10″ twist
- Surgeon short action detachable magazine bottom metal
- Badger Ordnance Maximized scope base
- Badger Ordnance Embedded Front Rail
- Surefire brake
- McMillan A5 stock
- Timney 510 trigger
- Spuhr ISMS mount
- Nightforce 3.5-15
- Harris bipod
To learn more about how I built this rifle, take a look at Building a Custom Remington 700 .308 Tactical Rifle.
WARNING: The loads shown are for informational purposes only. They are only safe in the rifle shown and may not be safe in yours. Consult appropriate load manuals prior to developing your own handloads. Rifleshooter.com and its authors, do not assume any responsibility, directly or indirectly for the safety of the readers attempting to follow any instructions or perform any of the tasks shown, or the use or misuse of any information contained herein, on this website.
Using a overall length gauge, I determined that in my rifle, the the bullet will touch the lands at an overall length 2.953″. This is far longer than a standard AICS magazine can accept (typically in the 2.850-2.885″ range depending on your magazine and how much space you want in front of the cartridges). Since the 195 TMK was primarily designed as a match cartridge (where each round is individually loaded) this isn’t much of an issue for single feed applications. Since some guys only shoot from magazines, I decided to see how it would perform at magazine length as well. For testing purposes I loaded two different overall lengths, 2.940″ (.013″ off the lands) and 2.880″ (fits in an AICS magazine, see image below). The decision to start .013″ off the lands was based off my experience with the other TMKs, which seemed to like a shorter jump. These are the same two overall lengths I used for the IMR 4064 load development post.
After carefully examining a wide range of data for 190 to 200 grain bullets in the 308 Winchester, I decided to work with 5 different charges from 40.5 grains to 42.5 grains in .5 grain increments. This was an educated guess based off of my experience and NOT the result of testing in a ballistics lab. These loads are shown for reference purposes only. Please READ THE DISCLAIMER on this site before proceeding.
Targets were 2″ orange dots targets placed at 100 yards. All shooting was done prone, from a bipod with a rear bag. The Nightforce 3.5-15 scope was set at 15x. All ballistic information was recorded with a MagnetoSpeed barrel mounted ballistic chronograph. Temperature was 53F.
I used 8 time fred Lapua brass sized with a Redding Competition Bushing Neck Die and Titanium Nitride bushing. This die prevents working too much of the case and has provided me long case life with all of the rifles I’ve used them for.
Primers are Wolf large rifle hand seated with a Sinclair priming tool. I’ve found them to work great for large rifle primer applications.
Results are shown below:
The groups are shown in order, from left to right, top to bottom in the photo above. A quick note on the top left target- prior to firing the rifle I cleaned it thoroughly including a scrub with JB Bore Paste. I’ve noticed this particular barrel likes a fouling shot after it is cleaned. Because of this, I did not include the high round in the group measurement, and only included the four rounds that were together.
Velocities ranged from 2,394 to 2,536 feet/second with an average velocity of 2,476 feet/second.
Standard deviation ranged from 4.5 to 16.5 feet/second with an average SD of 11.4 feet/second.
Groups size ranged from .356″ (.340 MOA) to 1.154″ (1.102 MOA) with an average group size of .741″ (.708 MOA).
Note the last two groups shown, both had extremely low sub 5 feet/second SD and had all rounds into one ragged hole with the exception of one flier.
The first four 2.940″ loads shot extremely well, I was pleasantly surprised.
While my results with Varget were similar to IMR 4064, the IMR 4064 had a slight edge on Varget in terms of velocity and group size.
To get a good idea of the advantages of the 195 TMK, take a look at the table comparing loads I’ve developed in the test rifle below (the 195 TMK load shown in the table was developed with IMR 4064):
Note how the 195 TMK has less drift than all of the loads shown it to 1,000 yards. A further discussion of this can be found in Sierra .308 195 gr. Tipped MatchKing (TMK) REVIEW and load development: 308 Winchester and IMR 4064.
195 TMK is a solid choice in 308 Winchester.
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