first batch of reloads

[Guest ronin]

I've found my 300 RUM prefers 165 -180 gr. I use 97 Gr of RL 25 with 165 Barnes VLC, 96 Gr of RL25 with the same in 180. Though, you sound like you just had a little blip at 88 gr. do you let the barrel cool between shots? How 'bout cleaning?

[AJ]

Re: first batch of reloads

That's why its called working up loads for the gun. You have to find the load the guns likes the best. Usually, it will shoot best at a particular velocity.

When the powder is ignited and the violent expansion of gasses takes place, the barrel will start to vibrate in a sine wave (~). The best you can hope for is to have the peak amplitude of the waves be as small as possible. This is the measurement of the top of the ^ to the bottom of the v. Different powder charges can reach certain frequencies in the steel that makes the barrel vibrate inconsistantly.

You will find that your groups will follow a sine wave also. If you plot your group size and play connect the dots, you will see how this is formed. Keep a log book and see if you can notice a pattern with your gun. In time you can eliminate a lot of testing by researching what velocity range or approximate pressure reading gives bad groups. Another benefit of the log book is to keep track of how many rounds have been fired in the barrel. You can see when accuracy deteriorates.

To fine tune your load, once you find the best group, work up and down in 1/2 grain increments, then in .1 grain increments to see what the ideal load is.

Like Ronin mentioned, barrel fouling can also play havock with group size. Its best to make the playing field level. Clean between each group and fire a fouling shot before each group. Keep things consistant.

Other things to keep in mind is ambient temperature and load pressure. If you develop a great load that is just under max pressure at 40 degF, you will probably have to reduce the powder level for summer shooting in 80 degF weather. The opposite is also true for loads developed in July may not be the same in December. You probably need to adjust a grain or two to match the load from before.

[AJ]

Re: first batch of reloads

Step that thing up to some 180 gr Scirocco or 200 gr Accubond bullets and fill the case with RL-25 and you will have a sweet combo on your hands.

[VTbowman]

Re: first batch of reloads

[ QUOTE ]

Step that thing up to some 180 gr Scirocco or 200 gr Accubond bullets and fill the case with RL-25 and you will have a sweet combo on your hands.

[/ QUOTE ]

Remington factory 180 Swift Sciroccos were great out of mine... 1/2" at 100.

Just my 2 cents.