TR and Palma Shooters:

peterdobson said:
Lapua GB491's have shot as well as any bullet with a varity of OALs, from 40 thou. off to 20 thou into rifling. It doesn't mean that your rifle will shoot them at all, as this is the nature of shooting. I think, generally, that a more generous leade is better, i.e Rule 150 chamber, although many fine results are obtained with Obermeyer specs.

Regards,

Peter Dobson
Hirsch Precision Inc.
Lapua in Canada, officially
Click to expand...
Can you remember Pete if the Wichita 'prefers' the Lapua 155's off the lands or with a jam?
I definitely must do something with my present match loads. I believe 2850 FPS, is a tad slow for 900 meters.
One half a grain incease of my powder, will give me almost a 100 FPS boost.

Cheers.......
 
Brutus, getting 100fps from a grain of powder is odd; I wonder if your load is centred around something "twitchy"? It'll be hard to get consistent velocities, if it's that sensitive to powder charge variations. What load are you using?

A Lapua 155 @ 2850fps is good enough for 900m shooting. Using a G7bc=0.236, in standard atmospheric conditions (sea level and 59F, which is more demanding than most target shooting) you can expect a 1000 yard (910m) velocity of 1202fps (which is supersonic; speed of sound is 1122fps) and 100 inches of drift in a 10mph crosswind (i.e. pretty standard .308/155 performance).

With a Lapua 155, you could go as low as 2750fps and still be supersonic at 1000 yards.
 
rnbra-shooter said:
Brutus, getting 100fps from a grain of powder is odd; I wonder if your load is centred around something "twitchy"? It'll be hard to get consistent velocities, if it's that sensitive to powder charge variations. What load are you using?

A Lapua 155 @ 2850fps is good enough for 900m shooting. Using a G7bc=0.236, in standard atmospheric conditions (sea level and 59F, which is more demanding than most target shooting) you can expect a 1000 yard (910m) velocity of 1202fps (which is supersonic; speed of sound is 1122fps) and 100 inches of drift in a 10mph crosswind (i.e. pretty standard .308/155 performance).

With a Lapua 155, you could go as low as 2750fps and still be supersonic at 1000 yards.
Click to expand...

Hm, thanks Pete first off. Maybe my OAL is what I should be adjusting.
Sorry rnba, one half a grain caused a little difference in velocity.
With an overall length of 2.77, (present chosen load) I was in an ever so slight contact of the front of the chamber.
I chronographed my rounds about two weeks before the match, and had an average of 2850 fps. There was a mean variance of some 20-25 FPS. I am using 44.0 grains of IMR 4064.
Just to add more info here, about three months back, I loaded the same bullets/same brass/same primers, with 44.5 grains of the same powder. Another different chrony recorded a varying average of 2900-2925 FPS. So I did drop my loan by one half a grain......(OAL of some 2.73 IIRC)
I am very new to this, in retrospect perhaps I just need more 'trigger time' at relatively long distances.
This September was my very first match at 900 meters. It's quite demanding shooting at this range with a TR.
It certainly did not help without a shooting jacket/glove & my first time with a new sling.
I have alot more work to do on shooting form and equipment than handloads, from what you fellas say here.
I did enjoy myself by the way! Everyone there was very friendly and helpful at the APRA Homestead range to this novice.

Thank you for the help and advice.

Cheers......
 
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Bulldog, it has been my experience that each rifle is different, even consecutivly numbered ones.

If you accept each is different, then it is not helpful to say "My Savage like this." or "My Krieger likes that."

A rifle shoots a particular bullet/load just because it does. It is meaningless to quote the barrel or rifle make. When I see a rifle shooting well, I want to know: Which bullet, which powder, what velocity and how far off/into the rifling.

With that ifo I can set up a quick survey of loads to see if my rifle likes the bullet/powder.
 
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