What's causing this please

[Vermincinerator]

The Blue stuff was actually pretty good, much better then what is available now.

 

Ian,

[bradders]

I don't know for sure but I'd guess at a mix of go/no-go gauges and vernier callipers.

 

 

I spent an hour with the lads in the London proof house comparing several sets of .223 gauges I have to theirs.

The reason I did this is because you'd think all off the shelf gauges would measure the same....but that would be too simple!!

 

Anyway, they showed me their process, and that is to gauge with Go and Nogo in both SAAMI and CiP. CiP is slightly tighter on headspace than SAAMI, and if it doesn't gauge on the latter, then it doesn't get a CiP stamp.

Then they drop a neck diameter gauge, a throat dia gauge and a throat oal gauge.

They're looking for tolerances that are too tight, not loose, so their test wouldn't necessarily pick up the issue with the chamber in the OP.

That would require a visual inspection of the chamber (not always easy) and the brass (once they've found it and picked it up of the ground).

 

There's no way of knowing at what stage the chamber in that rifle went bonkers, so it will all be just speculation.

The main thing is that the issue has been rectified satisfactorily and no one got hurt.

 

Everyone has good days and bad days you know.

[Laurie]

Nothing Hornady does shocks me. I wouldn't be surprised if that was exactly the case but, it was being sold here as well for a bit. It sucked wind like many other lots of Hornady 17HMR. It would pin-hole through rodents as close range. I quit shooting 17HMR because of it's unreliability. Don't feel like the bad 17HMR ammo is targeted to the UK. It's everywhere.~Andrew

 

 

Unless things have changed recently, all HMR ammo is manufactured by CCI irrespective of whose name is on the carton. The resulting implication is that there are good and bad production lots but not good and bad makes. All 17-cal bullets come from Hornady irrespective of the tip colour.

 

At the end of the day, it may simply be a bad idea to cold-swage the neck and shoulder into a 22WMR case to make it into a .17. As the priming compound goes in beforehand, the neck / shoulder can't be annealed for obvious reasons. (All .303 Cordite marks were made the same way as the bundle of cordite sticks had to be inserted before shoulder/neck-forming. I've seen the contents of sealed cases of surplus in excellent condition, nice and bright brass no corrosion at all, where one in three or even one in two cartridge necks had split over time the unannealed brass unable to take the tension involved in holding the bullet indefinitely.)

[Andrew]

Not sure I share your views on necking down the 22WMR case to 17HMR. CCI did it well for many years before this most recent rash of split necks. I shot it almost every day for the first two years of production -including the white box pre-production ammo. The first issues with the cartridge was lack of bullet expansion. Then later, came the split necks. They know how to do it right but are cutting corners someplace in the manufacturing/metallurgy department.~Andrew