243 blowing out primer pockets on reloads

[jcampbellsmith]

Esmith

I think you need to try some factory ammo and fire say 3 rounds in your rifle. Then measure the length of these cases to the .400 inch diameter on the shoulder. It should be somewhere between 1.620 and 1.630. If it's nowhere near these numbers then you have an issue with your chamber size. Without measuring the cases to the shoulder, how can you tell what type of sizing you are doing?

Have you any of these? http://www.hornady.com/assets/files/catalog/2009/69-70_precision_gauges.pdf

Secondly, I think you should trim all your cases to 2.035 inches or less.

Thirdly, I have seen primers being blown out of the primer pockets in .243 cases not trimmed correctly to length.

Good luck. JCS

 

[PREMOD70]

I will add to reload the fired factory cases not the ones fired in another rifle. Unless you know the history of the cases you may be reloading soft brass.

 

[bozo699]

I did not mean to mislead anyone. The brass I am/was using is once fired from a different rifle, but I feel I had prepped it properly. Full sized and trimmed. I will try neck sizing the once fired factory cases from my rifle. I will try different powders. I have some IMR 4895. I will check the roll crimp as well. I also plan to reclean the rifle.

I agree with Frank, something is WAY wrong and I'm missing it. I'm kind of worried to fire the rifle again. You can feel in on your face and VERY hard to open bolt when it happens.

Everett,
If this is the case don't mess with it anymore, have a smith do a chamber cast and go from there.
Wayne.

 

[CaptainMal]

This all sounds like a "dog chasing his tail".

There really is no such thing as "headspace trouble" with a fire-formed case in that chamber. First lower the load and jam a bullet, say .030", into the lands. You DO need the measuring tools to figure that. Hornady makes a good, inexpensive one.

Then you need to measure the shoulder of that fire-formed case. Again, something like the Hornady,
Sinclair or RCBS Precision MIC is ESSENTIAL to have and use properly.

After measurement of the shoulder, you then measure a sized case coming out of your die. It should be little more than .004" less than that fire-formed case. If much more you WILL blow primers with a headspace issue.

Just adjust the die to provide a proper re-sizing tolerance and all should be fine. If you have done little or none of the above, you haven't gone anywhere to solve the problem.

 

[Frankr]

Hey im just going to throw this out there as food for thought, because i was just talking to a action man this morning and he was telling me about a weak fireing pin spring causeing blown primers..

so maybe did you take the bolt apart clean & lube the fireing pin, maybe could be rusty or gumed up in there causeing a weak fireing pin hit and a blown primer.

 

[canuck]

You said brand new shells are no problem so I would suggest you NECK SIZE ONLY . I bet the problem goes away.....

 

[jonbearman]

cartridge length is supposed to be 2.045 at max and the neck unloaded should be .276. i WOULD TRIM TO 2.040 AT LEAST AND MAKE DARN SURE THAT THE BULLET MATCHES THE LOADING DATA.mY NOSLER MANUAL lists no load for h4350,however it lists imr4350 39-43 grains. It doesnt list varget as its a few years old.The most accurate powder tested for the 90's is imr4831.The 95's they list vvn560 as the choice and they show no h4350 for their loads only imr4350.You didnt switch h4350 for imr4350 did you.They are close but that only counts in handgrenades and horseshoes.Recalculate what powder you should be using and use the nosler manual.Just to be safe.

 

[expiper]

Listen to the adivce above....measure --measure--measure.....dont take anything for granted.....if it shoots factory ammo good and not your stuff ....do the math...you are gooofin up somwhere!!!.....try new reloader brass ....same load....your pressure is wayy tooo much for a minor over load with 4350 (either imr or H)....I had some cases that grew on me and had the same trubl.....dont forget the seater die can be causing this even if the ctgs are correct length...try a ctg with no bullet and see if it is crimping!!!!!.Roger

 

[bozo699]

Listen to the adivce above....measure --measure--measure.....dont take anything for granted.....if it shoots factory ammo good and not your stuff ....do the math...you are gooofin up somwhere!!!.....try new reloader brass ....same load....your pressure is wayy tooo much for a minor over load with 4350 (either imr or H)....I had some cases that grew on me and had the same trubl.....dont forget the seater die can be causing this even if the ctgs are correct length...try a ctg with no bullet and see if it is crimping!!!!!.Roger

Roger,
I have been making these suggestions since the beginning with no real conformation.
Wayne.

 

[Esmith]

Sorry I have not had a chance to work on this issue lately. I have read this over and over and talked with several local reloaders/shooters. I realize it is my load causing the issue. Hope to work/play with it this weekend. Will keep you all posted of my findings.