Thread: Kimber Load Development

Did some load develop of my sibling Kimbers in 280AI and 7mm08.



7mm08 loaded up some 162s at mag length did a quick ladder to attempt to find pressure limits and test Rl16 which the Internet seemed to have determined was too bulky for the 7mm08 case.

I didn't need up finding pressure but did model it in Quickload and stopped at the theoretical max load (above my Book data for the 162 by a fair bit but I'm seating longer. It's also only marginally more powder oddly than the book data for the 180 ELD so was pretty sure it would be OK especially coming up from lower down. Top load Velocity shows me a bit under 63kpsi so warm but nothing unreasonable and producing less bolt thrust than a 270 at full Saami pressure of 65kpsi.

Wasnt intending to use the upper end but without pressure signs and I ended up finding a node at the top load with a velocity of 2739 and an ES of 15 for 5 shots including a clean bore shot. First clean bore shot (CLP and then brake cleaner to make sure chamber wasn't lubed) went high but the following 4 shots went into .784 so will load a few extra up to check to see how close to pressure signs I am but if I'm not right on a pressure spike I will LOAD UP. Few more groups around this node to try dial it in and play with seating depth. It's turned the 7mm08 into quite a potent little rifle. My shoulders feeling it even with only 25 shots fire (it's 2.6kgs all up)



Somehow I forgot to take a picture of groups will take one when I get home.

Then a ran a ladder with the 280AI and 180 ELD m at mag length with RL26. Used some Peterson brass which is lower case capacity as such I ran into early pressure (a slight swipe just visible under the right light but there all the same) slightly earlier than expected at 59.5grains. I may try the norma I have to see if I can get to the node that kimbers seem to have around 2860fps. There was a bit of node at 2750 where 4 shots where touching with loads from 57 to 58.5 grains but considering its got an extra 2 inchs of barrel vs the 7mm08 I'd really like to get to the next node if possible to warrant the extra heft and length as realistically the 7mm08 isn't that far behind. Was quite nice to shoot however with the bit of extra weight from the scope and with the brake fitted. Definitely kicks less than the 7mm08 with bare barrel.

I've been considering suppressing the 7mm08 but these groups and velocities have me wondering if its too risky to loose the 3inchs of barrel and potentially these groups. I will see what this load can do and if I can get it to 1/2 inch I'll likely leave it and suck up the recoil.

Anyone had much experience with a rifle that shoots in the sub moa range then cutting and suppressing it and the effects on handloads accuracy. Being on the edge of pressure I'm a bit scared if I cut it down I might lose this upper pressure node and potentially loose way more velocity than I'd like.

Will update as things progress.