My brother and i went out shooting at the 50 yard range. Being out of Blackhorn, i took an assortment of powder tubes filled with 80gr 3F American Pioneer and 90gr 3f American Pioneer. Also brought along Winchester W209 primers and CCI 209M primers.
My brother took his first 3 shots with his V2 Accura with 90gr APP 3F, 245gr Aerotip Powerbelt and the CCI 209M primers. Group size wasn't good for 50 yards Sooooooo,

Recovered CCI 209M primers,
So after the shots with the CCI 209M primers, i decided to show him how a primer can make a difference. He kept saying Holy Bleep! After each shot so i took that as a good thing.
Fired 3 more shots and as you can see, TOUCHING!!
Winchester W209 primer group,
Recovered Primers,
W209 and CCI 209M primers side by side,
We fired 13 shots total through the rifle trying 90gr APP 3F & 80gr APP 3F with the two different primers, then we went and swabbed the bore out and came out again with 90gr 3F American Pioneer and the W209 primers and this time, My beloved 300gr Thor.
3 shot group @ 50 yards,
Recovered primers,
All the shot primers from today,
One heck of a day playing around and shooting gentleman!
Now before i went out, i obviously knew that if i did not make some adjustments, it WOULD have been filthy due to the shortness of the CCI 209M primers.
I adjusted the firing pin bushing out to take up that space and this is actually adjusted a little to much, but it takes a Firm Snap at closing it up in order for the hammer to pull back.
This picture was taken after we fired 16 shots through the gun with the W209 and CCI 209M primers.
This shows a better view of how much i had to adjust, it needs to be screwed in at least half a turn to get the right fit. Then again, those recovered primers were the cleanest I have EVER seen on any rifle i have.
As for me, i chickened out after 3 shots with my .54cal CVA Mountain Stalker. I shot 80gr 3F American Pioneer, CCI #11 Cap and .015" TC patches lubed with Barricade/A touch of Wonderlube.

I was to excited to shoot any more after that LOL.