sabotloader

It was raining all morning but I really had a need to do some shooting so I headed to the farm.

Tom had cleaned out one of the out buildings, the only things left under the canopy was a PU camper and boat... I was able to back under the canopy in the camper section - open the tailgate and the my canopy cover and work off my tailgate work bench and everything stayed dry.

I set the bench up in the next stall in fronto of the boat and walked the target out 35 paces - which I thought would be somewhare near 25 yards.... I do not pace for a living and it is a good thing - cause a was a bit farther than 25 yards. When I ranged it at the end of shooting with the range finder it was 37/38 yards.

The goal was to sight in a new Nikon Omega on a Knight DISC 50 and I also wanted to test a new Chrono that has not worked right the last two trips out.... I was reading a 3 digit number and that was really bothering me... I sent a email to Competition Electronics and the service tech very politely said - "you dummy... you have it set on meters/second" he didn't say "you dummy' but after him telling me what was wrong I know he was thinking that.... i didn't even know it could measure 'meters/second' Well anyway, he told me the key strokes to get it back to feet/second and now everything is good.

Anyway got the target out and the chrono setup and commenced to shooting. I was shooting the last of a box of 300 grain XTP's and I was going to shoot both BH and T7 - I decided to shoot 110 grain of both powders just for drill. Thought it would be a good place to start sighting the scope in.

The other experiment was I was going to use 7 different primers just to see if there were any big differences in velocities.

I did save the hotter primers to shoot the BH with but just for grins I decided to try a couple of Winchester T7 primers - just to see how they would do... no problems at all - instant ignition.



Nothing out of this world, but I was really surprised at the differences on velocities... I was sure that the BH loads would be a bit hooter than the T7 loads. I was using a HPH-24 sabot for all shots and this is a very snug sabot in this DISC Elite. I made a point of compressing the loads, both T7 and BH.

But, when you look at the velocities - I begin to wonder.... 110 grains must be the point just at turn over where 120 grains of BH will create a greater velocity with this 300 grain bullet than does 120 grains of T7. Looking back on one of my earlier spread sheets 120 BH does move the velocity faster than 120 T7.

Anyway it was a great rainy day activity... i advise it for everyone.

Semisane

Good report Sabotloader, and some fine shooting. The velocity results blew me away. Do you recall what the two powder difference is with 120 grains?

cayugad

The velocity is interesting. The rifle is accurate. I think a Knight has to be pushed. Now in my 22 inch barrel 90 grains seems to be magic. In my 24 inch barrel then we step up to 100 grains. I suspect Knights are powder hogs.

sabotloader

Semi

Here is a target shot with 120 of each... But this is the Extreme not the Elite - if that makes a difference...

saxman1

I couldn't believe the valoscity diff @ 100 grn
The BH really shines @ 120 grn
Nice shooting and great report as usual.

gregrn43

Nice shooting and very good report/

wabi

Interesting!
Looks like the T-7 loads reach the point of max efficiency with 110 gr. Beyond that you're just making a lot of smoke & recoil for little gain in velocity.
The BH-209 is still burning efficiently at 120 gr.

TNHagies

I have done the same with the same results. One time I even TRIED to create a hangfire w/BH. Shot ML primers with a loose conical and stopped the seating pressure when I felt it hit the powder. Still perfect ignition. Not sure why some people have problems and others do not.

Good info and I was surprised by the velocity as well.

lemoyne

This is very interesting, an excellent report and a good experiment. The part of it that is very interesting to me is that it confirms what I have done the velocities are a bit different but considering 5000 feet difference in sea level thats to be expected. The gap between 110 and 120 is the same on both powders. I believe that it is because thats the point where the pressure makes BH burn progressively with efficiency . Do you concur Mike?

spaniel

The message I take away from that is that if you are conservative in your loads, you'd better have a reason other than velocity to use BH209 because you'll be paying a lot more for similar performance.

At the top end, however, you WILL get more velocity from BH209 and if you're willing to pay for performance you will get it.

To get the BH209 velocities shown at 120gr you'd have to use about 130gr of 777. I get 1950 fps with a 325gr bullet from a 26" barrel and 135gr 777. I'd point out that the max load for 777 is supposed to be 135gr so at "max charge", 135gr 777 and 120gr BH209, their velocity is about the same. I know some people use more BH209 than 120gr but I'm going by recommended limits here.

It is clear that the velocity curve (fps gained per grain of powder) for BH209 is better than 777 at the top end.