Author Topic: Pierced primer Hornaday 270 Superformance (Read 1162 times)

jgrass · « **on:** May 22, 2011, 06:37:00 AM »

Has this happened to anyone else? All three shots, pierced primer, 270 Win 130-Superformance. What should I check out.

Thanks,

JGrass

mauser98us · « **Reply #1 on:** May 22, 2011, 07:10:56 AM »

Could be many things. Soft primer,load too hot for YOUR rifle.too much firing pin protrusion,bullet engaging rifling as you chamber,weather and on and on.Do you handload? Is this a factory chambered rifle or custom? Chamber could have been cut on the minimum size causing issues too.

Swampman · « **Reply #2 on:** May 22, 2011, 07:19:52 AM »

I tried some because it was all I could find. It wasn't very accurate.

jgrass · « **Reply #3 on:** May 22, 2011, 07:35:40 AM »

The rifle is a pre-64 M70 1958 ish, good shape, not fired much, original, headspace ck'd good, pin protrusion looks like my other ones( 06 and 308), pin may not be as radiused as much but does'nt appear to be protruding any further. Standard New England spring day 65 degrees. May be too hot for my rifle?

I do hand load but its been a few years, just getting back into it.
JGrass

mauser98us · « **Reply #4 on:** May 22, 2011, 05:13:08 PM »

Each rifle is a law unto itself. That ammo may just be too hot for your rig.

gunnut69 · « **Reply #5 on:** May 22, 2011, 08:35:49 PM »

I spoke to this on your other thread but it seems you've covered many of the possibilities. I would masure the protrusion and check the fit of the pin in the boltface. If you've not had the bolt apart recently then it's likely OK. Has the rifle handled other ammo OK? If so it may well be as mauser98us suggested, the load you were firing may simply be to hot, generating too much pressure in your particular rifle.. What could cause this we've also spoken to, loaded too long and jamming the bullet into the throat, too tight a neck (possible but not likely), or simply a bad lot of primers from the factory.. The ammo your using is loaded to maximize velocity and high pressures can result from such endevors.. Also in looking at the photo this appears a pressure related incident as there is a scape on the case head just to the left of the '270' that appears to be caused by the ejector hole. This means pressure were high enough to flow brass into the ejector and cause the marks. Also the primer is quite flattened indicating fairly high pressure levels. If the rifle has been fired with other ammo then it's almost surely the ammos fault and contacting the company would be the way to go.

jgrass · « **Reply #6 on:** May 23, 2011, 07:16:16 AM »

Thank you gentlemen,

I have not tried other ammo yet. I am waiting for some Remington managed recoil ammo to come in from Cabala's. I'll give that a try next. I did inspect the firing pin closer and found it was protruding appox. .012 more than the -06 and was not as radius'd as well. It has some machine marks on it too. I will polish the tip this week before I shoot with the Remington ammo.

Thank you,
JGrass

Frank46 · « **Reply #7 on:** May 24, 2011, 06:03:30 PM »

Check the tip of the firing pin out. Could have divits or pits from the gas cutting the tip of the pin. And see if those missing pieces of primer aren't inside the bolt. Met a guy at the range who was shooting some black hills 223. Each primer had the hole you showed. Took the bolt apart and knocked the bolt on the wood bench. Out came the disks from the primers and the firing pin was gas cut. Frank

jgrass · « **Reply #8 on:** May 25, 2011, 07:40:42 PM »

Thanks Frank, did not think of that! No gas cutting but have to check for the little disc's. Pin protrusion after polishing is appox. 050-.055.

Thanks, JGrass

Goatwhiskers · « **Reply #9 on:** May 26, 2011, 12:57:13 PM »

Were these handloads? I see R-P, Winchester, and Hornady brass. If they are, better do some checking. If they are someone else's handloads, all bets are off. Goatwhiskers Well nevermind, looking again there's three different calibers.

Ethan · « **Reply #10 on:** May 26, 2011, 02:12:52 PM »

This is a little off topic but I tried the Superformence my self I tried it in both my Browning A-bolt and Tikka 595 in 243 and neither shot better then 1 1/2 in. which is decent by both guns can do much better.

jgrass · « **Reply #11 on:** July 27, 2011, 05:55:07 AM »

All good with the Winchester M70-270 after polishing pin to .054"(started @ .064"). No issues with factory ammo, Hornaday Superformance, Federal, Remington and Winchester. All shoot under 2 1/2". Good for my hunting.
BTW having trouble uploading pic's. I'll keep trying.

Thanks to all,

JGrass

STUMPJMPR · « **Reply #12 on:** July 27, 2011, 08:31:10 AM »

Looking at the pictures it appears the load is too hot for the gun. Notice how flat the primer is. I would shoot standard velocity ammo. Those new maxed out loads don't kill them any more dead.

gunnut69 · « **Reply #13 on:** July 27, 2011, 06:36:01 PM »

The Superformance ammo is loaded to the ragged edga and any slight problem is magnfied.. Personnaly I've never found the 270 needed more power... I guess the .010 off the length and the reconture is the difference between a safe load and a dangerous situation. I almost always prefer the 130 Partition and a stiff charge of IMR4350 and I like CCI primers.. I've owned several 270's but unfortunately someone always wanted them more than I needed them. The result was a hole in the ole battery.. I'm finishing a 270 as we speak.. The action was a 721 that started life a 30-06 but was rotted to death..Corrosive ammo??? The barrels a Douglas and the stock a laminated and greatly lightened one from an unknown maker. The bottom metal was a DBM unit from a Ebay auction.. The stock is finished but needed the forearm lightening cuts stiffened..and checkered. The Metal needs a bit of finish but it's basically ready to go. I'll let you all know how it comes out.. Perhaps a new deer shooter for this year.??

Graybeard · « **Reply #14 on:** July 27, 2011, 07:11:57 PM »

Hornady SuperPerformance like the Light Mag ammo before it operates within SAAMI specs same as all other manufacturer's ammo. They use special powder blends to alter the pressure rise curve but do not use higher pressure.

Think of regular ammo pressure curve as an inverted V and of SuperPerformance more as a U. The pressure average for time in barrel is greater tho peak pressure is the same.

gunnut69 · « **Reply #15 on:** July 28, 2011, 06:54:36 AM »

GB's absolutely right but that said the ammo is loaded to the upper edge of the standards.. That plus the extended pressure curve and a firing pin nose a bit too flat and sharp edged caused the puntured primers. When all is said and done there is added stress and a longer duration for whatever stress is generated. This makes rifle condition and tolerances greater concerns. I am of the opinion and I concede it's just an opinion, that if one needs more power just use a bigger cartridge. I don't hotrod reloads and don't like the factories doing so either. Any handloader can and does make the occasional mistake, When a factory does so the quantity is simply a lot greater. The SuperFormance type ammo eliminates some of the safety marjin built into the ammo and the rifles. This is similar to some of the hotrod wildcats and the exagerated claims thru the years. Most were done up in well built custom rifles built with very tight tolerances. When those rifles were duplicated, sometimes with less adherance to tolerances overpressure took its toll. That of course was overpressure stress but the ammo in question produces a near maximum pressure for a greater percentage of the bore time for the bullet..and stress is cumulitive, just bend a wire until it fails. The outcome is still not know. Most modern rifles made with modern steels will take a lot of abuse but then all 270 caliber (and other calibers) rifles are not modern.

Graybeard · « **Reply #16 on:** July 28, 2011, 01:30:32 PM »

I've not shot any of the Super Performance ammo yet but sure do like the older Light Mag ammo. It has always been some of the most accurate ammo I've tried. It will generally shoot better in my rifles than I can attain using selected handloads. It's all I use in 7-08 for hunting these days but my supply will run out eventually and they don't make an equivilent SP load as now they load only the SST and monolitic bullets in the SP line. I have always preferred their standard interlock spitzer.

gunnut69 · « **Reply #17 on:** July 29, 2011, 12:07:12 PM »

GB= it's always been my observation that should I find a load that works well or does especially well in my gun they will soon discontinue or alter it.. so rule one-buy all you can afford. Same with magazines--I always buy way more than necessary as they will soon be unobtainable or ridiculously priced.. Ny favortie 10 Ga. mag turkey load was the Supreme load from Winchester with a 2 1/4 oz. charge of no.4 shot at the normal velocity.. An honest 65 yard killer..and closer even better!! Unfortunately the high velocity loads don't pattern nearly as well and shotguns live and die by number of hits not the individual pellets energy.. Haven't been able to locate them for a couple of years. Have several boxes (see rule one) in stock but eventually I will find the bottom of the last box... I suppose it's not as important now as turkey hunting is nearly impossible for me now. My desire to get new knees was reaching a new high when the wife had one of hers replaced..now I'm not so sure..

Graybeard · « **Reply #18 on:** July 29, 2011, 12:25:25 PM »

I picked up five extra boxes over what I had on hand a few years back. Reckon I should have gotten more. If I don't hunt anymore than I have done in the recent years I still might have a life time supply. It's not by any means the only rifle I have to use either.

gunnut69 · « **Reply #19 on:** July 29, 2011, 12:46:43 PM »

I bought a M7 Remington in 7-08 a few years back as a donor for a mannlicher project for a future son in law. The s-i-l turned out to be a jerk so that's not gonna happen but the project is still on. I've not owned a 7-08 for long enough to try it out but worked up a load for a frend a few years back and was impressed. The 280 has always been a favorite but perhaps a short action version is in order.. Anyway have a great weekend, I need to get back to the shop..