The test was done on my basic match load:

PPU Cases neck sized

WLR Primers

VARGET (ADI AR2208) Powder 

174 Sierra MatchKing

3.07 inch OAL

Powder charges varied from 39.4 to 42.1 grains, in 0.3 grain increments. Testing was done at 600 yards off the bench.

While my long time standard match load of 40.0 grains did well, I found it was close to a scatter node of 39.7 grains (three shot group of nearly 3 MOA). 

I picked 40.6 grains from this test and shot this load at the June D-Day match. 

In looking back thru the data, I realized that 40.3 grains would have been a better choice because 40.9 grains showed a significant elevation and deflection shift (up and right). 

So, I loaded up 40 rounds of 40.3 grains and test fired this load yesterday along with the 40.6 grain load I’ve been using this year. I tested these loads at 300 and 600 yds, the two distances the CMP Vintage Sniper Matches are shot at. 

The results were quite conclusive, 40.3 grains shot better than both my 40.0 grain standard match load for the No. 4 and 40.6 grains that I had selected from the OCW test.  This was evident in both windage and elevation spreads at 300 and 600 yards. 

While the objective of the OCW test is to find the “accuracy nodes”, it’s also to find “scatter nodes” where groups tend to scatter.  You want a load that is far enough away from the scatter nodes. 

The far line of targets is at 600 yards.

Here is the 300 yard result with the 40.3 grain Varget load. One shot slipped just outside the 10 ring, the dreaded Nine Point Nine. 

Here is 600 yards. I paid no attention to the wind, and it shows, which was quite variable in strength from 2 to 3 O’Clock. But all shots within the height of the 10 ring. 

A 99 at 300 and 97 at 600 yds is a fairly respectable score for vintage sniper. But it won’t win the match when you’re up against the 1903 A1 with 8x Unertl scope.  But, this should give ‘em a run for their money.

I’m still learning how best to hold the rifle in this shooting position (prone off a sand bag rest). I’m finding a good solid grip and pull the rifle back into the shoulder with the right hand and grasp the back of the butt with the left hand from under the right shoulder (for a right handed shooter).  It’s extremely important to keep consistent head pressure on the cheek piece, else the vertical spread of the groups increase. 

Temp - 80 deg F

Mean Velocity.     2416 fps

Extreme Spread.     39 fps

Standard Deviation  12 fps

The other thing I discovered is that this 40.3 grain load has a trajectory that exactly corresponds to the scope elevation setting of “3” for 300 and “6” for 600 yards. Very convenient, no chance of losing zero’s this way, which I have seen happen with two very good shooters with 1903A1’s during a sniper match. 

As odd as it might sound, I don’t see a correlation of muzzle velocity with vertical position of bullet impact on the target (within the same charge weight) with this load in the T.  Obviously, larger deviations in powder charge do make a difference, but it needs to be more than +/- 0.1 grains to show up on the target.

Based on the OCW tests, the vertical change in group MPI at 600 yards was 3.6 MOA over a 2.4 grain charge weight range. That averages out to 1.5 MOA/grain. For charge weights thrown within +/- 0.1 grains, that’s just +/- 0.15 MOA (less than one inch at 600 yds).  That’s hardly noticeable for these rifles. However, there are OCW nodes where adjacent charge weights show group MPI clustered together.  That’s the whole point of doing the OCW test. 

I found that 40.0, 40.3, 40.6 and 40.9 grains loads all shot into a group of just 1.8 MOA vertical extreme spread of all 12 shots (three shots for each load). Pretty remarkable.  Goes to show that weighing charges does not do what we think it does….

I have some testing to do for the .303's. I have some Norma 202 powder.

Unfortunately I don't get regular access to the 200m range. But will probably base my test around the 40 grains mark and see how it goes.

But may not get the chance this year!

Are you loading SMKs?  They seem to be very consistent when loaded to 2400 fps.   This would be at lower pressures than Mk 7 ammunition produce.  The SMK runs about 50 fps faster when substituted for the Mk 7 bullet in Mk 7 ball ammo (i.e. pulling the Mk 7 bullet from the cartridge and seating the SMK in it's place, keeping the original powder in the case).  

Yes I use 174 grain SMK's. I will take another look at the Norma load data.

I can probably check velocity at my local range. It's 50 metres only; but ok for a velocity check.

I loaded some 7.62 for the L39A1 recently. 40 gr of TU 5000 under 147 grain NATO type ogives. A first test at 50m showed 0.5 inch variation in elevation; for 10 rounds. Which I think is worth taking to the 200 m range for a proper test.

1/2 inch group at 50m, that's 1 MOA which I expect is pretty tough to beat for any L39.  Sounds like you have an excellent rifle Shaun.  

I've never used Vectan powders before.  But from what I see, TU5000 is in the burn rate range of IMR 4895 to IMR 4064 which should be just right with a 147 to 168 gr bullet.  40 grains would be mild too, less strain on the action and easy on the barrel. 

I was able to shrink the groups a bit further by concentrating on a firm hold.  The scope elevation setting is bang on at indicated range with this 40.3 grain Varget load with 174 SMK. Makes it easy to just dial in “3” for 300 and “6” for 600 yds.  Hard to screw up. 

Best of luck Geoff. Keep us informed of the results.

Glad I saw this before getting proud and posting pics of my IPSC plate groups! LOL 

Next will be a bullet seating depth round robin test to see if there is an optimal seating depth. 

The objective is to consistently get muzzle velocity Extreme Spread to within 30 FPS to reduce the vertical point of impact dispersion at 600 yards. 

I’ve ruled out cartridge case weight variations. For the round robin test done on powder charge weight, I checked all the cases fired that day.  Of the 25 rounds fired, the max weight was 168.7 gr and min was 164.1 for am extreme spread of 4.6 grains. Muzzle Velocity and Elevation POI had no correlation with case weight. 

I’ve chosen 40.5 grains of Varget charge weight for the bullet seating depth test that gave the least amount of vertical spread of POI at 600 yds for a targeted mean velocity of 2410 fps. That selection came from the plot below. I’m expecting a slight velocity increase with the deeper bullet seating depths so I dropped the 40.6 grain charge by 0.1 grains to try and stay away from that elevation step up that occurs around 2430 fps.  In the plot below, the cartridge OAL was 3.07 inches. 

I measured the throat length on the No. 4 T, now at 1700 total rounds fired, with a Hornady Bullet Comparator and OAL Gage. The 174 gr SMK contacts the lands at 2.708 inch Cartridge Base to Ogive of the bullet. 

Here are the bullet seating depths (all dimensions in inches) I’ve chosen and approx cartridge overall length.  Note the bullet jump to the lands is quite a bit, such is the nature of the Lee Enfield chamber and throat dimensions:

Load #   CBTO   OAL    Jump

   1        2.470  3.050   0.238

   2        2.475  3.055   0.233

   3        2.480  3.060   0.228

   4        2.485  3.065   0.223

   5        2.490  3.070   0.218

I’m really not expecting to see much correlation of seating depth to muzzle velocity variation, but I want to rule this out and see if there is a seating depth that brings tighter groups at 600 yards. 

Weather permitting, I’ll run the ladder test on Friday.

how do you like the garman - ive been thinking to get something - is it difficult to use ? remember im old and not overly tech savvy 

Mike, I really like the Garmin, it works great and is supposed to be very accurate. The best thing is the simplicity. Set it down beside the rifle pointing down range, that’s it.  A few simple menu selections to make. You can link it to your smart phone to save all the data.

As to temp variations during the ladder tests, it’s quite minimal, no more than a few degrees. Varget is quite temp stable, and I have verified this.  

Doing these tests in a “round Robin” method spreads out the environmental changes evenly to all test loads. And that’s also the case for barrel heating and fouling. In the round robin method, you shoot one shot of each different load, then shoot the second shot of each load, and so on.  What you DON’T want to do is shoot all shots of load 1, then all shots of load 2 as barrel and environment are changing and that can affect results. 

as to that round robin - im going to use that with my 4570 loads that im working up this winter , thanks , in the past we always shot groups of five in succession , probably fine for our cowboy loads but i can see that round robin helping with my long range ammo 

Keep on doing this its forming a body of knowledge in depth.Thank you