winchester palma load

[stu_bear2002]

hi all, could anyone tell me how many fps i could expect to be getting using factory winchester nraa 155 grainer's for the .308 from a 26 inch barrel as i don't have access to a chronograph and i am looking at making a cheat card to affix to my stock.

[Guest]

Hi Stuart,
A hugh guess mate as it depends upon the load, the barrel ( ie dimensions ) the steel (ie ss or chr moly,) etc
My guess would be between 2800 and 2860.
BTW what is a " cheat card " a new one to me.
Barry

[stu_bear2002]

Thanks Barry, the load would be the one made for the nraa by winchester which i believe is made up with the sierra 155mk , 45.5gr of 2208, in a winchester case. As for the cheat card, just another term i guess for a trajectory card with bullet drop, click values, velocity and wind deflection. I made one using a ballistics program for an old 6.5x55 zeroed for 300 yards that gave me hold-over or click adjustments required when i changed distance, the best thing was that you could change the altitude for different ranges around the country for example castlemaine would be 900ft and swdra would be around 70 ft above sea level (some will no doubt argue this) does make slight changes in the POI.

[mike H]

Found this one very interesting. My observations are that all this data recording, calculating, is OK to a point. After a while a lot of data emerges showing elevation settings for different distances, and different ranges. These are good to start your sighters with, however if things don`t go exactly to the book, trust your rifle and your judgement, and make a change. Why it is, I am not even going to worry about it, however if your shots are not waterline, straight across the middle,it`s time to pull yourself together and try to do something about it.

[stu_bear2002]

Just to clarify something up in my post regarding the "cheat card", it's only used to get me on target then i would be making the final adjustments. i have just acquired a chronograph over the weekend whilst away at work so i can now check all my velocity's and get the right data for each one of my loads. so it looks like I'm out on the farm during the week to do a bit of testing.

[pjifl]

People often forget temperature. Especially at long range.

An early start in the cool will usually have an elevation noticeably lower than the same range near midday.

I often see people place too much emphasis on the elevation recorded in the cool and refuse to make enough change early enough in the second shoot.

There is nothing like good record keeping to get on target but you have to trust the rifle. Remember the most important shots are your sighters. And the first one 'usually' goes 1/2 min low from a fresh barrel. Get to know your barrel characteristics.

Peter Smith.

[stu_bear2002]

I have changed tactic somewhat from the original post and have just developed a cheat card using point blank software and an F-1 chronograph. I am hoping to use this load on Saturday at Castlemaine (my initiation to the sport) . The load in question is the factory made winchester 150 gr super X load, which from my barrel (26 inch) gave me an avg velocity of 2836 fps, The highest velocity being 2859 fps and the lowest was 2812 fps, Unfortunately i didn't have to many rounds on hand at the time so i concentrated on getting my elevation right at a given range (8 inches high @ 60 yards) and recording the velocity of each shot. I hope to get another day in before Saturday for a bit more testing at longer distances and for my wind-age, with a bit of luck it wont be as windy as the first day of testing .