Primer Problem?

[Tumbleweed]

Hi guys, I've got one for you. I have a 1/3 to 1/2 MOA load in my 300 ultra using 210VLD's. I use Nosler Custom brass, H-1000 and Fed 215 Gold Medal Magnum primers. I regularly shoot at a life sized plywood bull elk anywhere from 700-970 meters here on the farm where I live. It has been great practice on shot placement and wind reading skills. I shoot just one shot and normally hit the vital area at all of these distances. Occasionally I may dial a tad too much or not enough wind, but they have all been "kill shots." The elevation is normally spot on. A few weeks ago a fired one shot at 730 meters and did not hit the elk, this was with no wind and great conditions. I couldn't explain why this happened so I kind of discounted it as a primer issue. I fired a pair a couple of days ago at 700 meters that were 2 and 3/4 inches apart dead center in my bullseye, good enough, no problems. Tonight I fired a shot at the elk placed at 968 meters and saw my shot impact low in the grass behind the vitals. By my calculations the bullet was roughly 2moa low of where it should have impacted. Atmospheric conditions have been the same lately, calculations in the scope were done correctly before the shot and the correct hold in the reticle was used. I looked my case over good and discovered that it has a very faint extractor mark and almost no crater in the primer which normally I have a pretty nice ext mark and the primer is cratered. The load is safe, never had any sticky bolt and it is highly accurate. I decided to pull a couple bullets to make sure nothing weird happened with the powder charge and found that the charge was perfect just as I expected. My only conclusion at this point is that I have come across a couple of weak primers lately, will this cause a velocity drop this significant?

 

[SBruce]

Good question and good practice principles.

I suppose that a primer could fail occasionally, just as some bullets occasionally fail. I imagine nothing is perfect (as much as we'd like it to be anyway).

I'd be curious to hear if anyone else has seen primer variance, and if so.....how much velocity loss? Or was it just discounted as an error on the shooters part.??

I've only ever had one handload fail to fire due to a primer, but have had a few factory loads fail to fire due to a "dud" primer. I've had totally unexpected fliers and misses occasionally myself and no concrete evidence as to why. They coudn't even be repeated.

Hope you get some good responses back on this one.

 

[Kevin Thomas]

Tumbleweed,

How many rounds, as in groups, have you fired here? No problem with your practice regimine, which sounds pretty reasonable for hunting/training. However, to truly evaluate the load, you need to fire some significant numbers into groups at these distances and see what happens. In long range (1000 yard) competition, you'll need to spend a pretty significant amount of time sorting through various lots of primers to find the one that works best. I'm not saying Remington 9 1/2s vs, Fed 215s, vs WLRMs here, either. I'm talking several different lots of 215s, etc., to see which one works best. I seriously doubt that you've gotten any "bad" primers here, but I have no doubt whatsoever that you've run across some that performed significantly better than others of the same brand and make. You need to isolate that lot, and glom onto whatever amount you can for your more critical shooting. Many of these issues are completely invisible at shorter distances, but will pop up in a heartbeat when you stretch the ranges a bit. Give it a try, and see what turns up.

 

[davewilson]

about a month ago i had my gun go "click" this happened to me a couple years ago and found it was a weak spring, and it happened very often. my first thought was a repeat but long story short was the primer fired and simply didn't ignite the powder enough to explode.when i took the shell apart, the bottom maybe 1/3 of the powder was clumped together and blackened. quite visible and different from the powder in the upper 2/3's of the case. a very good dent in the primer and my spring still has 26 lbs which i did have checked to be on the safe side. the primer went off, but simply didn't ignite the powder. Edge case, 99 gr of H1000, GM215M primer.

 

[Tumbleweed]

Thanks guys, I definately agree with the fact that there will be variances from primer to primer of the same kind. However this will be very small differences in point of impact just as Kevin mentioned. We're talking 2 to 2.5 moa low on that last shot! From what I've heard, primers either fire or they don't, never heard of a weak one. This gun is very consistent and accurate, these two unexplained "drop outs" make me nervous. My elk hunt out here starts this coming Saturday and I will be sitting on a 340ish Roosevelt that only presents a shot between 970 and 1020 yards. I am well prepared for this shot, but I sure don't need any funny business with components at the last minute. I'll have another chance to shoot Friday and see if I have any more problems. Any more ideas are welcome!

 

[gahlizard]

my shooting partner and i have been struggling with a similar problem. we both have custom rifles bulit with quality components in 338RUM and EDGE, shooting 300smks @ 2780 and 2850...both shoot 3/8 to 1/2 moa VERY consistantly at the very comfortable temps around 45-70 degrees. the problem shows up below these temps. around 20 degrees, everything goes south. we have looked into the extra clothes, cold fingers etc, but no real solution other than to keep the hunting ranges closer at colder temps. he shoots retumbo and i shoot h1000...we both run Fed gmm.

 

[Tumbleweed]

Well, I think I may have discovered what caused my two "drop out" shots. I remembered that I carried the same three shells in my rifle during the deer season out here. One of those evening hunts was very wet. Because of the way I position my shells in the ammo box, I know that the same shell I used when shooting at my target elk was one that had gotten very wet. My theory is that water managed to get around the primer and either cause a problem with the primer itself or dampen the powder. This so far seems to make sense, any of you guys experienced this with damp powder?

 

[bassin93]

Tumbleweed, not true on the idea that primers either fire or do not. The primer must be struck with the same amount of force each time or it will not ignite the same. I know this from shooting Black powder cartridge rifle sihloette matches. I was in the middle of a match and my shots started to go everywhere except where I was aiming. Mike Venturino who you may or may not know, he is a noted gun writer, came over to me and told me to check my firing pin in my sharps, he said it is probably broken which is evident by the erractic pattern I was shooting and explained as to why. The broken pin would not strike the primer with the same force each time and would therefore ignite differently. I replaced the pin and accuracy returned. My .02 worth