300HH

[safarihunter]

Although I promised myself not to engage in "best gun/cal for Africa" debate-for me it's a no brainer: 375HH/ 300HH- end of story and debate, I am interested in some thoughts about a problem with my 300HH:
Custom ammo from a very well established ,well known/respected company-not one round fires- pull trigger- click is all I get-every single round-I'm told "it's a head space issue-" OK- so I went to another company- also well respected, etc- same problem!!
I then obtained ammo from Cabelas( Federal) and Midway( Nosler) and no problem except one round from Nosler
Before you ask: I checked everything I know to check: Length, seating, overall weight, etc. The custom ammo companies will not divulge primer, powder information because of legal/insurance issues.
Possible explanations given to me: military primers were used-whatever that means; lube may have gotten into the cases- but in all and by both companies?!!!
Any thoughts from the experts out there?!!

 

[TERMINATOR]

Although I promised myself not to engage in "best gun/cal for Africa" debate-for me it's a no brainer: 375HH/ 300HH- end of story and debate, I am interested in some thoughts about a problem with my 300HH:
Custom ammo from a very well established ,well known/respected company-not one round fires- pull trigger- click is all I get-every single round-I'm told "it's a head space issue-" OK- so I went to another company- also well respected, etc- same problem!!
I then obtained ammo from Cabelas( Federal) and Midway( Nosler) and no problem except one round from Nosler
Before you ask: I checked everything I know to check: Length, seating, overall weight, etc. The custom ammo companies will not divulge primer, powder information because of legal/insurance issues.
Possible explanations given to me: military primers were used-whatever that means; lube may have gotten into the cases- but in all and by both companies?!!!
Any thoughts from the experts out there?!!

Personally I would rule out issues with the ammo like "Lube into cases" because you have experinced the issue across several brands of ammo. Besides, lube in a case would not prevent a primer from firing, it would mainly affect powder burn. Now getting LUBE ON THE PRIMERS when handling them can cause primers to fail to ignite, but still the odds of this happening across brands of ammo are slim and if that were the issue I would be demanding my money back from the ammo provider.

I would be looking at firing pin or something else that is preventing the pin from making solid strike against the primer. (Chamber tolerance error allowing the cartridge to sit too far forward?)

If you know somebody else with a .300 H&H you could try the ammo in their gun to confirm the ammo is good or not. A little harder to do than if you were talking about a .30-06 or .270 given it would be easy to find a friend with one, but it would be good to try the ammo in another .300 H&H which would confirm ammo vs. rifle issue.

I still say it is in the mechanics of your rifle's firing system.

To me this has to be something about the mechanics of the firing pin striking the primer and the custom ammo may be more prone to it because it might be closer to the exact chamber specs????

 

[Uncompahgre]

How well did the firing pin impact the primer on the misfires versus the rounds that did go off? Is this a new rifle or an old one that has functioned well for several years with other ammo? You might just have a dirty firing pin or a weak firing pin spring. My experience with "headspace problems" with belted magnums is case separation and not misfires because belted magnums are headspaced off the belt and not the shoulder as with other cartridges. This is very true with the 300 H&H and the 375 H&H because there is basically no defined shoulder to headspace from and it is my understanding that is why H&H put a belt on them in the first place.

 

[PHOENIX PHIL]

Although I promised myself not to engage in "best gun/cal for Africa" debate-for me it's a no brainer: 375HH/ 300HH- end of story and debate, I am interested in some thoughts about a problem with my 300HH:
Custom ammo from a very well established ,well known/respected company-not one round fires- pull trigger- click is all I get-every single round-I'm told "it's a head space issue-" OK- so I went to another company- also well respected, etc- same problem!!
I then obtained ammo from Cabelas( Federal) and Midway( Nosler) and no problem except one round from Nosler
Before you ask: I checked everything I know to check: Length, seating, overall weight, etc. The custom ammo companies will not divulge primer, powder information because of legal/insurance issues.
Possible explanations given to me: military primers were used-whatever that means; lube may have gotten into the cases- but in all and by both companies?!!!
Any thoughts from the experts out there?!!

Not an expert, but some thoughts. I never had a misfire in any of my rifles until a few months ago. I reload and use Fed 215 primers for my magnum calibers exclusively. That is until a few months ago when they became very difficult to find. I decided to give Remington 9 1/2M primers a try. This is when I started to have an issue. A long story made short, the physical dimensions of the Rem's are different than the Fed 215's and I was led to believe after scouring the web that I wasn't seating the primers deep enough. Since then I've made a concious effort to make sure the primer is seated just so that it is slightly below the flush line of case head, i.e. a bit deeper.

Now I don't think you had a problem with factory ammo not having the primer seated deep enough. But what led me in this direction to begin with was I noticed that the misfired rounds had a noticeable difference in the depth and size of the dimple in the primer after firing. The depth and overall diameter were smaller. If the primer was indeed not seated properly, i.e. not deep enough, then some amount of energy from the firing pin was being used up pushing the primer deeper into the pocket and not actually "denting" the primer. This would explain the smaller dimple. This is a long winded suggestion that you compare the dimples on the misfired rounds (if you still have them) to the succesfully fired rounds. If they're noticeably different, then of course this will still bring you to the question of why?

It would definitely eliminate this case lube theory which I agree is a stretch to have happened with two different lots from two different factories. But I could buy into the military primer idea if those primers are actually harder and would require greater striking force to ignite them. Perhaps more force than your rifles firing pin hits them with.

Another thought in my mind would be the firing pin spring. The spring is what causes the firing pin to move forward and strike the primer. If the spring were starting to lose strength it might not be able to push the pin with enough energy to ignite the primer. You made no mention of the rifle. How old is it and more importantly could you guesstimate how many rounds have been fired in it? Perhaps the spring needs replaced?

 

[TERMINATOR]

How well did the firing pin impact the primer on the misfires versus the rounds that did go off? Is this a new rifle or an old one that has functioned well for several years with other ammo? You might just have a dirty firing pin or a weak firing pin spring. My experience with "headspace problems" with belted magnums is case separation and not misfires because belted magnums are headspaced off the belt and not the shoulder as with other cartridges. This is very true with the 300 H&H and the 375 H&H because there is basically no defined shoulder to headspace from and it is my understanding that is why H&H put a belt on them in the first place.

Yes, given the belt on the H&H calibers is the thing holding the cartridge in place rather than the non-existant "shoulder" the only way the cartridge could be sitting to far forward is if the chamber was out of spec tolerance to where the belt came to rest. If this was a rifle that has prior fired correctly than that is most likely not the case.

If it is a new rifle it is a long shot but the chamber could have a mfg defect letting the cartridge sit too far forward.

But in the end I am still suspecting firing pin or firing pin spring issues.

 

[James.Grage]

Phoenix Phil and Terminator have very good check points.

When reloading do you make sure the primer hole is cleaned out?

I have had many issues with Federal primers while loading shot shells. There shape was causing problems in my Perazzi shot gun...however upon closer inspection it was the shells them selves as the primer was off center in some of the rounds and all i needed to do was spin the shell 180 degrees and it would go off...this issue was taken to federal many times and after 1 to 2 misfires in a round of 25 i have changed shot-shell ammunition to Remington...and i used to buy about 50 flats a year of federal to shoot.

Items that we went through is firing pin - Spring. need to be checked and replaced...the wear on a firing pin only need to be a few MM to cause problems...

The many gun smiths said after looking at and replacing the firing pin and springs take a selection for brands and go to the firing range and see what one work..and stay with that brand...

Make sure that you re-leave the tension on your firing pin spring when in storage..

 

[TERMINATOR]

Make sure that you re-leave the tension on your firing pin spring when in storage..

LOL...great reminder...your comment made me go back and check all my rifles!

 

[James.Grage]

The thing that we all need to look at is not every one reloads there rifle ammunition...

As with shot guns all rifles are sensitive to bullet manufacture and bullet make...

if you do not reload you need to grab a bunch of manufactures bullet styles and go to the rifle range and have a go at 25 - 50 - 100 - 200 yards with the makes of bullets...

i have learned to start short and gradually move out...some times starting at 100 yards you will not hit paper...

 

[RayAtkinson]

I also am an avid 300 H&H fan..Been shooting an old pre 64 Mod. 70 for over 60 years now. With proper handloading only the 300 Wby can best it, and that's only on paper, in the field all the 300s perform about the same.

I suspect your chamber is a tad long and the firing pin is pushing the belt forward to the chamber. Any good gunsmith can trouble shoot that gun for you. Weak firing pin spring, short firing pin, bad ammo can cause the problems you describe, but would have to have the gun in hand to figure it out..