Suggestions on starting load

[Stan_TheGunNut]

I recently completed assembling a 300/221 upper for my AR. Given the wildcat nature of this cartridge and the many variables associated with developing loads, I thought I'd ask here for advice on what a good starting load might be? I intend on shooting 99+% subsonic, and have some 220 and 240 grain SMK's on hand to use. I also have some brass made that I hope will work. Bascially, my questions are which powder would you all suggest, and how much of it, to start with?

The AR that I assembled uses on of TP555's barrels with the adjustable gas block in the pistol position. The barrel is 12 inches long and I'll be using it on my SBR'd AR. Currently installed in the lower is an H2 buffer and the carrier is a FA one that I had laying around. Currently this setup is unfired, as I haven't loaded any rounds yet. Starting out will be unsupressed, but eventually I plan on using my silencer.

I'll be happy to post the results once I get things running.
Thanks.

[Alleycat]

9.9 grs of VV N110.....

[rv10flyer]

Send me a PM with your email address and I will send you the load data from the Sierra manual (I tried to upload the pdf here but it is too big; only 85 KB). It has data for both the 220 and 240 SMK's.

I'm using almost the same load that Alleycat posted.

[dvanncvann]

10 gr 0f ww296 with 220 gr. projectile.

[Scalce]

http://listmequick.com/300/Sierra300whisper.pdf