OzFclass

omark 44 TR rifle 308
26" 1/13 twist
ar2208 @ 45.5gn [might go up to 46]
winchester cases
currently using federal gold match primers.
155gr projectiles

is it worth using magnum primers to get a better/cleaner burn ?

advantages ? -
disadvantages ? -

regards

LR.

ps: sorry about the missing info.

Hello,
It's likely that magnum primers would increase your sd and es. Many people go the other way and use the Palma cases with small primers to improve es and sd. I assume you are talking about 308 from the stats you have given?

I have tried the magnum primers in my Omark. I ended up giving most of them away. I've settled on the cci br2 primers in lapua cases. I am using 2206h but. They have increased and stabilized muzzle velocities and the barrel is a lot easier to clean. But the later is probably more about the powder than the primers.

its certainly not in a 308, but in a 280AI, using 180 gr Bergers and AR2213sc, trying Fed Magnum LR primers gave me an extra 50fps (Avg over about 20 shots) compared to Fed 210 Match primers.......along with about double the ES.

Do a primer test first with a minimum of 5 shot groups with say, 4 different primers because every barrel is different. Do this at 100 yards if you must, but I prefer 140 yards using your 45.5 grains of 2208 in the Omark. You will soon see what the barrel likes. You can dispense with the chronograph as the group size with the least elevation is what you are looking for.

Having determined what primer works best then you can proceed to varying powder charges using the chronograph. You don`t need a target here as the bullets can just be be fired as single shots over the chronograph in .2 grain graduations. What is important is to collect the chronograph readings and plot them as a graph in the computer program Excel or manually with velocity V`s charge.

It is where you see relative flat sections in this graph, your best load will be found. I use these flat sections to re-examine, powder charge in those areas in five shot groups at 140 yards. I find the best charge and then do a seating depth test in .005`` graduations at the basic level.

The only time I've heard good things about magnum primers is with slow powders in large cases. And when I say large, larger than 7 Shehane. I bought a 1000 each of CCI 250s and Fed 215Ms to try 2 years ago. As with Tony's experience, they increased velocity in two ways, one of them being spread . All I've found them good for is fire-forming cases - you need less powder .

AlanF wrote:The only time I've heard good things about magnum primers is with slow powders in large cases. And when I say large, larger than 7 Shehane. I bought a 1000 each of CCI 250s and Fed 215Ms to try 2 years ago. As with Tony's experience, they increased velocity in two ways, one of them being spread . All I've found them good for is fire-forming cases - you need less powder .

I use Federal Gold Medal Match,GM215 M,primers in my Match Rifle loads with 2209 powder,I have had good results over the years,I have tried the CCI-250's,in the same situation,uniformity of velocities was not as good as the Federal GM215M primers and grouping was noticeably wider. Today I am past worrying,just use the Federal GM 215M and take what comes.
With 155 grain bullets and 2208 or 2206H,I use Federal GM210M primers.
Testing standard F/Class type loads with standard Federal 210 primers versus Gold Medal Match 210 primers,I have always found a difference in chronographed results and on the target.The Federal GM210M always being ahead.
Mike.

Federal 215M primers are great for a .375 Cheytac and 140gn of AR2218. But I think they are a bit of an overkill in a .308 win.

I have just loaded up some test/development rounds for my 284 using 180 hybrids 2209 and 215 magnums. Velocities were pretty consistent, ES & SD were 30/12 (highest) 9/3 (lowest) and everywhere in between (total of 50 rounds). However all groups were consistent and tight (between1/4 - 3/4moa @ 100) regardless of ES&SD's. I put the crap shots that opened up the groups down to ME. So I loaded another 24 rounds up the next week for a recent club shoot @600m and potted 59.4 (clean barrel) and then a 60.7 in relatively good conditions but far from perfect (vertical was between 1" - 1 1/2"). That was the load with the ES/SD 9/3 measured on the clubs Ohler35 chrony and near enough to 2830fps.
Of interest, things that I have been concentrating on with all 3 of my calibres (284/6BR/308) are consistency with neck tension (annealing necks/trimming necks square/neck turning) , consistent case volume I have sorted my cases from lightest to heaviest (yet to check volume) but keep them in that order in their boxes, consistent seating depth and consistent projectile run out. All pretty basic and run of the mill, but "consistency" (components ie ammo etc and application ie you the shooter and your imputs to the rifle when shooting) is a major key to success. At this stage I will test another 50 rounds, 10 rounds at each 300,5,7,8,9m and see what it brings.

If you are interested in what the results bring, let me know and I will keep you informed.

Out of interest I originally bought 3000 215m's for use in my 338 Lap and thought I would give them a run in the 284 as I had read some interesting articles from the USA where people where having good success with the 215 magnum primers in various calibres (generally the larger slightly over bore ones) in their f open rigs - and these had been sitting in my cabinet for the last 8 years almost untouched (300 used in the 338).

If this load/combination keeps performing I have no intention of trying the 210's I will just continue to use the 215's. Also shoot what ever works for you and your rifle even if it is unconventional and not the norm.

Hope this helps,

John.