The UK's Finest Independent Forum for Shooters and Gun Owners. Est 2010.

Good challenge Dromnia

On reflection I doubt that the co-efficient was as much a factor than the size
though friction co-efficient is the combined affectof materials the brass - lead and brass - nickel etc is not readily listed.

Nominal spec for 9mmP is .355 and the lead bullets we shot tended to be sized .356 or even .357. This was mostly due to the cases thinning out after numerous reloads

What I did find that a crimp setting that worked fine with lead was inadequate with copper wash or FMJ. It cost me a national championship when I stupidly swopped out lead for copper washed jackets and I experienced exactly the problem I described.

The photo does however show that several thing could be at play
1. the feed angle may bevwrong or
2. even that the slippage under the extractor could be hampered by a burr or spring tension

Comparing lead and jacketed is like comparing apple and oranges.

In regards to crimping it is the "spring back" of the materials that needs to be considered when applying crimp.

For taper crimped rounds then the case/boolit/bullet fit should give the required retention and the taper crimp is only to aid feeding.

When using a roll crimp the quality and shape of the crimp groove on lead boolits and the cannelure on jacketed in relation to the crimp die that is important.

Just as an additional thing to consider.

How are you crimping the loads?

I use a Lee ( yes I know...) taper crimp die and use quite a good crimp based on the hammering the rounds get by the blowback action.

I didnt measure the OAL for my gun, just used SAAMI spec length.


Mike

It's a Lee factory crimp, was set at just under 1/2 a turn, I've increased it to just over a full turn and re-crimped all the rounds, there's now a definite slight indentation on the copper plated heads.

Won't get to try it until tomorrow as my club is closed today :(

Got an email from Viking this morning, they can either send a firing pin to the RFD I bought the Henry off or havi collected and returned from him. I asked if they could just send me the pin but they say they only deal with trade not public!. So, hopefully should get it this week and off we go again :)

Still can't get my head round the fact it has a problem with reloaded ammo, there are millions of 9mm guns about, I've shot back street knock off copies of Glock and Beretta that probably cost less than $10 to make in the far east and they cycled anything I threw in them. Also can't see why the bolt has to be so big/heavy with such a powerful spring, it really does hammer the rounds into the chamber, again I've shot small 9mm handguns with tiny springs and no weight and they all cycle fine, the Beretta Storm and Spikes rifles I use in the US are much "lighter" on the amount of force they use to load rounds.

Just looked at the pics of your gun. I'd reckon you'd need a heavier crimp on your loaded ammo either jacketed or cast. On top of which, having owned previously three SGC straight pulls, you might want to give the feed ramp and the edge of the chamber mouth a little bit of a polish making sure there are no burrs and a lovely smooth surface.....

As for the heavy bolt and heavy spring, it has to be so as your gun is a simple blow back to extract and eject the case. It's the weight of the bolt and the strength of the spring that keep the bolt closed at peak pressure, hence safe.

Cheers :)

I'll get the polishing stuff out and give it a good going over!.

Are you shooting it at the Mayfair? If so i can sort you out some factory ammo for testing?

I've never had the particular problem you've mentioned with mine, but i've got a 1st Gen Uzi mag version and i've only used factory ammo in it. Mine works like a Swiss watch when plinking at the range, but as soon as i use it in a competition i normally get a jam every other mag (Normally the hammer hasn't been cocked but a live round has been chambered) :roll: I don't know if i'm limp-wristing it, the 115gr rounds don't have enough poke or what, but i was hoping to solve this when i eventually get around to reloading my own, maybe not :cool2:

Just been considering my working practices with the gun.

I dont know if its relevant but I have to keep mine scrupulously clean or I get the odd malfunction, usually a fail to feed/ stovepipe may be due to the bolt travelling slowly if its dirty.

Mike

Mark, yes indeed, hoping to get there tonight about 6:30 and give it another go with the re-crimped rounds.

Mike, Absolutely spotless, was new and clean when I got it, I stripped, cleaned with CLP and then lightly lubed it so it's slick as a buttery thing made with extra butter.

Blackstuff wrote:Are you shooting it at the Mayfair? If so i can sort you out some factory ammo for testing?

Is that the indoor range in Sunderland? Is that place still going?!! I used to shoot there over 20 years ago! Bought a Star Firestar off them and had my eye on an H&K P9S, but got posted South....