.338 RUM H1000 300smk issues..

[chuck plissken]

ok,Im having a rifle built and just loading up some test/break-in loads with Sierras manual. Im getting a compressed load very soon at COAL of 3.580. Im curious if the manual really wants this to be seated longer cause it doesn't seem right to me.

powder is 3 years old and another pound I have is less than 1 year..hope the lot of powder isn't different?

I started at 84.0,85.0,86.0 with 5 loads in each to start and break-in along with chorno results. I was gonna stop at last 5 loads of 87.0gr which would be a total of 20 rounds for a first time out and recording data. But...87.0gr is just where it started to "crunch" or feel compressed...

Sierra lists 93.9 as max loading for this combo at 3.580"!!!

Im wondering if anyone will chime in on similar issues with this manual/combo. Im gonna load some using "off the lands" method once I receive the rifle and break-in. Im sure I will be able to squeeze more in there.

thanks for any help or reassurance

 

[Broz]

I question the 93.9 gr of H-1000 with a 300 SMK in a RUM. I have never seen a 338 Lapua or an EDGE go past 93 without pressure so I would be very skeptical of that load. Are you sure that was not for 250 gr bullets?

I would say a 338 rum will max out closer to 89 gr.

Jeff

 

[chuck plissken]

hey Jeff,i hear ya. i triple checked and it is the 300gr.

i agree on the 89gr max. wierd how Sierra lists a longer COAL with 300gr for the 338 win mag as a single shot...doesnt for the RUM though.