Why the "Click" .."Bang"?

[blackbird]

Hi, have been home loading for about 5yrs but recently started loading for my .300 win mag. 180grn load are fine with N160 powder but loading 220grn bullet with 52.5 grns of N560 powder the test shot replies with an off putting click from the firing pin...pause then the bang. The round performs ok but does anyone know the reason for the pause. Don't want the next "Click Bang" to be my😉 thanks guys

[Turnup]

Hang fires can happen occasionally, which is exactly why all shooters are (should be) trained to hold on aim and NOT OPEN THE BREECH after the click - timing varies from 10 to 30 seconds depending on whom is talking. Never had a hang fire take even close to 10 seconds - in my experience with metallic carts (rimfire and centrefire) the delay has been only a little more than long enough to notice, so well less than one second. I suspect that the 30 second timing comes from times gone by when mercury fulminate primers were the norm, but this is pure speculation on my part.

Usually a one-off and I have seen no learned discussion as to why they happen in metallic cartridge guns. If your reloads give repeatable hang fires then someone might be interested in doing some research on them.

Hang fires in muzzle loaders are much more common. In percussion guns usually attributed to blocked nipple, and in flintlocks usually attributed to over full or blocked vent hole (and in matchlocks hang fires are pretty much a design feature!).

[loiner1965]

are you using the same powder / bullet combination
is it happening all the time or just a few out of a batch
can be alot of things like .....primer not fully seated or damp case prior to filling with powder etc

[pbranthwaite]

52 grains isn't a lot in a big case like 300WM, perhaps the delay is the primer flash reaching the powder?

[tacfoley]

Why are you shooting such noticeably-reduced charge?

The Vihtavuori manual notes that the lowest charge should be 69.8gr of N160 for this weight of bullet.....

Sometimes, having a too low charge can be as risky as too much. The phenomenum of surface detonation has been known to wreck revolvers, when the flash from the primer ignites the entire surface area of a powder charge lying at the 'bottom' of the case, rather than sequentially initiating a burn-through from the bottom of a column of propellant.

When I make reduced loads of H4198 in my .45-70 Govt, I ensure that the charge is packed into the case by using a scrunched-up paper filler to take up the space between the bottom of the bullet and the top of the charge.

tac

[blackbird]

Why are you shooting such noticeably-reduced charge?

The Vihtavuori manual notes that the lowest charge should be 69.8gr of N160 for this weight of bullet.....

Sometimes, having a too low charge can be as risky as too much. The phenomenum of surface detonation has been known to wreck revolvers, when the flash from the primer ignites the entire surface area of a powder charge lying at the 'bottom' of the case, rather than sequentially initiating a burn-through from the bottom of a column of propellant.

When I make reduced loads of H4198 in my .45-70 Govt, I ensure that the charge is packed into the case by using a scrunched-up paper filler to take up the space between the bottom of the bullet and the top of the charge.

tac

Thanks for the reply however this data was for N560 and as it was a heavier bullet and different powder I wanted to start at the low end and work up rather than going to the max.

[loiner1965]

Why are you shooting such noticeably-reduced charge?

The Vihtavuori manual notes that the lowest charge should be 69.8gr of N160 for this weight of bullet.....

Sometimes, having a too low charge can be as risky as too much. The phenomenum of surface detonation has been known to wreck revolvers, when the flash from the primer ignites the entire surface area of a powder charge lying at the 'bottom' of the case, rather than sequentially initiating a burn-through from the bottom of a column of propellant.

When I make reduced loads of H4198 in my .45-70 Govt, I ensure that the charge is packed into the case by using a scrunched-up paper filler to take up the space between the bottom of the bullet and the top of the charge.

tac

like tac i have used reduced charges in big cases eg..15gns trailboss in a .577/450 case which can hold 120gns of powder and everything was ok
what i use to do with some powders was to make a circular disc out of cigarette paper and place over the powder before i use a filler to take up the airspace.
some powders are case sensitive and you dont want a flash over which is when the primer flame goes over the top of the lying down powder and ig
nites from the bullet end.
with my martini henry reloading i now fill the case with 60 / 70 / 85gns of bp (still load developing lol) and take the airspace up with backer foam which comes in rolls so i chop off 15mm to 20mm depending on load.
i use to use kapok but fellow shooters complain of the confetti lol

[blackbird]

52 grains isn't a lot in a big case like 300WM, perhaps the delay is the primer flash reaching the powder?

Thanks for the replies, I was taking the data from the Vihtavuori web site however couldn't find round nose bullets. I have taken data now for different bullet type ( still not round nose ) and increased charge to 70gr powder before click bang stopped😳 it must be down to, as you say the large case, little powder and the time it takes to ignite. For the record the data for HPBT starts at 52.5gr but the data for the same weight match bullet starts at mid 60s, the max for the other bullet type is less than this....why??? There's plenty of room and no more weight in the bullet for the same powder. Is it to do with accuracy? I can't see it is the usual safety reason. Sorry if I am sounding stupid but asking the question is the only way to get an answer. Thanks again for all your help😉