Strange barrel heat?

[Lucky6547]

Bought a brand new CZ 527 Varmint in 17 Hornet.
Got my hands on some factory 20gr ammo and headed to the range.
Was amazed at the accuracy. Second group at 100 yards after zeroing was 0.150" ctc . Couldn't believe a factory gun with factory ammo would shoot like that. Decided to see how it groups with a warm barrel since it is for varmints and sometimes it'll be shot with a warm barrel. My other larger cal rifles get warm from the chamber forward...but this gun was cool to the touch at the chamber area and muzzle, but warm near the forend of the stock...anyone with a 17 hornet have a similar experience? The attached pic is just showing off...

 

[memo43]

How much of a gap is there in the stock where its warming up. Maybe the stock is retaining heat an allowing it to radiate up towards the barrel?

 

[Lucky6547]

It's free floated from the factory...plenty of space...more than 1/16" less than 1/8"...

 

[amlevin]

I have the same thing happening in my .223 Bolt action as well as .308. This phenomena is a function of where most of your powder charge is burning. It starts in the case/chamber but finishes in the barrel. Use a slower powder and this "warm spot" will move closer to the muzzle and with a faster powder back toward the breech.

Ideally you will have complete powder burn just as the bullet leaves the crown.

 

[searcher]

Nice pic! You got a good one. I just ran my first rounds through my CZ last week and found the unleaded ammo shot better than the leaded - but not that good. No notice of what you describe though.

 

[Fotheringill]

Searcher-

Check your torque. CZ is a bit sloppy with its settings when leaving the factory. See your manual for suggested settings.