Armory Sponsor
Posted: 9/23/2010 4:43:20 PM EDT
|
Just figured I would share .... I loaded up some 450 Bushmaster cases the other day with the same 250g Flex Tip projectile used in the factory loads. I wanted to mimic the same velocities used in factory ammo so that I would not have to change the zero for my personal loads, and I still have several boxes of factory ammo left. The die set that I am using is the Hornady 4 die set. The brass is once fired Hornady brass that I uniformed the primer pocket, deburred the flash hole, and slightly champhered the mouth of the case. I then hand primed each case with CCI Small Rifle Magnum primers. All of the primer pockets were nice and tight (the way I like it!). Using my RCBS Chargemaster - each case was charged with 34g of Hodgdon's Lil' Gun. There was plenty of room in the case after the charge to seat the bullet. I used my Lee hand press to seat each bullet to 2.26" so that they would fit nicely into the AR magazine. After seating the bullets - I then used the taper crimp die, provided in the Hornady set, to apply a moderate crimp so that there would be no problems with OAL changing while rounds are being fired. I also loaded some 300g Hornady XTP projectiles using the same procedures during this sitting. With no starting data for this load - I used 29g of Lil' Gun to begin with. At the range today - I had my Crony set up to get the speeds of factory ammo to begin compare to. Clocking five rounds - the factory ammo's velocity was 2145 fps. I then loaded the five 250g hand-loads - checking the velocity after firing - the 34g of Lil' Gun produced an average velocity of 2155 fps. The primers were not flattened and there were no pressure signs at all. The point of impact was also identical to the factory loads. I then loaded the five rounds of 300g XTP rounds over 29g of Lil' Gun. These rounds produced and average velocity of 1775 with no signs of pressure either (primers still very round). The POI on these loads was very close (1" lower) than the other two prior tested ammo (this was surprising). With the lack of any pressure signs on this load - I am going to conduct some more tests at a later date. I believe it would be possible to get 1900 fps, maybe 1950 fps, using the 300g XTP projectiles without any negative effects. Overall - I was very impressed that the first load that I used produced results nearly identical to the factory loads (saved a ton of time). The 300g XTP rounds look very promising and considering I had no data for it - there is a lot of room for improvement. I am looking to pick up some 185g bullets to load up reduced recoil rounds. I really enjoy loading for this cartridge because of the ease of working with a straight walled case. Also - being a common diameter bullet leaves lots of additional options out there. This is by no means finished, but I wanted to put this data out there so that others with this caliber would have a starting spot without having to do too much to tailor to their needs. Sarg |
Armory Sponsor