I worked up a load for my 300 rum. using rl25 powder. I went by the Barnes data, and went 1.5 grs. above the max. for there X bullet, as sugested. I use my crony and the top speed using 90.5 gr's of rl 25 powder was 3204 fps. This is 100 fps slower than my load for 180 gr. Accu-bonds using 94 gr. of rl. 25. My question is, why can you not load the barnes TSX bullet's the same as the nosler 180 gr. Accu-Bond's, seeing as they are the same weight and both are spitzer bullet's.???? I have been only reloading for a only a year and i stick to the manual's 100% , but Barnes really has no data, other than bumping up there X bullet data. I may have to check my crony with other load's that i know the MV of, just to make sure it is working rite. I checked the load's for my 180 gr. accu-bond using 90 gr. and the MV was 3179 fps. sort of blow's the theory that the new barnes TSX is 50 to 100 fps. quicker than other bullet's.(as advertised) What i was trying to accomplish was working this load up to match my 180 gr. Accu-bond's , which i shoot at 3304 fps. Any info would be apreciated, thank's:Rick.

Here are my 180gr tsx results in my two 300ultramags.

I finalized my loads today.
Rifle #1-88gr r-25 3360fps
rifle #2-93gr r-25 3380fps

It seemed very strange that with 5 gr difference both rifles produced nearly the same velocity.I was using different lot#'s of powder but when using other bullets the charge weights were almost identical even using the two lot#'s.It seems that for some reason,one rifle develops much more pressure with the tsx's.

quote:

My question is, why can you not load the barnes TSX bullet's the same as the nosler 180 gr. Accu-Bond's, seeing as they are the same weight and both are spitzer bullet's.????

My guess on that would be the solid copper construction. It causes higher pressure to swage the buller to your bore. You will notice that the Winchester failsafe data is always slower than other bullets of the same weight for this reason.

quote:

My question is, why can you not load the barnes TSX bullet's the same as the nosler 180 gr. Accu-Bond's, seeing as they are the same weight and both are spitzer bullet's.????

You can use the same starting loads and work up while watching for pressure signs.As you can see from my previous post my load for one rifle is only 88gr or r-25.Using 90gr of r-25 in this rifle resulted in pressure signs appearing.Yet in my other rifle, no pressure signs showed until 95gr of r-25 was used.As such I backed the load off for that rifle to 93gr.As you can see both rifles produced very similar velocities despite the 5gr difference.That is why one showld not assume that all loads listed in the manual are safe for your rifle.

There are a lot of variables on speed such as barrel length of your gun compared to the test gun. Customer service at Barnes told me to use 3 grains more powder with the TSXs and it works in my rifle. The problem is the extra speed is not as accurate for me. Give them a call or send them an email. They will reply.

Remember, Velocity is a pressure sign. Probably the best one. If your rifle comfortably acheives 3304 with Accubonds you most likely could load TSX's to the same velocity and be within the same pressure limits as the Accubonds.
The TSX's can be somewhat similar to a Moly-Coated bullet. Since they are easier to move down the bore it can take a little more powder to push them as fast as a bullet with more resistance. You can often acheive even higher velocities but with a comensurate increase in powder charge...............DJ

Please remember that the TSX will usually penetrate better than the Accubond. I have read where you should downsize one size if using the TSX vs. a bonded bullet. Therefore I have changed to the 168 instead of the 180 for elk and increased my velocity in doing so. I think Hughjass is right about the softness of the copper in the TSX creating more pressure. Also make sure you are seating the TSX .050 off the lands.