AO Cold Bore Challenge
 

This challenge taken from another forum ... has been modified here to make it more doable (you can google the original ...which required five groups...in the Target and Precision section of the other forum). The challenge is to demonstrate that your rifle can put the first three shots on a given day, inside a 1” diameter target at 100M (or yards if that’s what’s ..available).
The RULES
*cartridge must be Alberta Big Game legal
*must be the first three shots (cold bore plus two) on three different days.
*must use a bipod or other “field rest...ie: backpack/post/jacket ...front rest.
*may use a rear bag
*Requires three target dots on a single panel
Please post successful (or close to successful) attempts.
To get started, draw three 1” diameter circles on a plain sheet of paper and take nine cartridges to the Range.

Sounds like a fun challenge but can you clarify that it has to be 3 groups of three on three separate days?

Also, I know it’s your challenge and all but wouldn’t it be better to keep it all “field condition shooting”? If you’re using a pack or bipod then using a rear bag shouldn’t be allowed, just to keep with the theme of things. Just thinking out loud here.

Yes, three groups total on one sheet of paper...so one three shot group on each day. I should have added that each group should have the date recorded near it.
The “original” specifies that a rear bag can be used so I left this one the same. As “easy” as this seems at first blush, I expect many will find it pretty challenging. The original challenge which required targets shot on five different days had only one successful participant. That challenge had 113 replies, was viewed over 6800 times, most over a one year period ...but keep in mind there is no time limit.

Barrel restrictions? Is varmint ok, or just sporter weight?

No restrictions on firearm style, barrel contour ....other than it must be chambered with a cartridge that is Alberta Big Game legal so 24cal/6mm and up.

.416 Rigs?

Sure...should buck wind.

I’m going to give it a shot. I wish I still had my Christensen Arms Ridgeline 280ai, that rifle was the most accurate cold bore rifle I had. I have a couple that might work out.

That cold bore shot has so much potential to be the spoiler....which gets more complicated when it has to be shot on an entirely different day.

I agree, most of my rifles take a shot before settling in, that’s where my Christensen would shine.

Slowly but surely.

How much do you guys really find cold vs warm even matters. Clean, oiled and unfouled vs fouled definately has some change, but how much change do you see in cold fouled vs warm fouled in a quality rifle

Usually not much difference between the cold bore (fouled) and warmed bore (fouled) in a good barrel ... probably less difference as the contour increases in diameter. I think a bit of oil increases pressure?

I would agree that there is less difference in thicker barrels. Not sure if it's pressure or lubrication or something else, or the absence of fouling.

Thought I would update with the information I recorded today. Chronographed a bunch of shots where I cleaned out all burnt powder residue before each shot, and then I shot a bunch with fouling. Consistently about 25fps slower muzzle velocities in a non-fouled barrel. Not sure what the difference would be for velocities when there may be hundreds of rounds between cleaning, but it would apply for the people that clean after every outing.

Kurt, I’m just working up a load for my CA Ridgeline in 280Ack.

What load did yours LOVE?