Problems help please.

stalkinginengland

Well-Known Member
Ok, A week or two ago I put a post up about tight cases when closing the bolt of my 243. I had some great groups but the case was not right so I have turned the sizer very slightly to push the shoulders back a little and this has helped the cases fit and they fit well. The new problem is that the groups are now shocking, can't get any better than 2 inch. Have tried bringing the powder charge up from the low end 37.7 again upto 41.5 The best being 39 grains which was where i was to begin with, which are still the best , but still crap.

I am loading 39 grains of IMR 4320 with 75 grain BT hornady cci primer in a fedral case.

Where do I start from, where do I look first?

Regards

Mark
 
How far off the lands is the bullet, in my 243 it liked to be 10 thou off the lands, this measurement can dramatically improve a group, cut mine in half once I found the sweet spot. deerwarden
 
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Corerectly set F/L sizing die is set so that the base touches the top of the shell holder whan the ram is at TDC, so how do you manage to set the dies to bump the shoulder when the its a set distance from the die shoulder to the base?
Unless your dies were incorrectly set up initially.

Ian.
 
Ok, A week or two ago I put a post up about tight cases when closing the bolt of my 243. I had some great groups but the case was not right so I have turned the sizer very slightly to push the shoulders back a little and this has helped the cases fit and they fit well. The new problem is that the groups are now shocking, can't get any better than 2 inch. Have tried bringing the powder charge up from the low end 37.7 again upto 41.5 The best being 39 grains which was where i was to begin with, which are still the best , but still crap.

I am loading 39 grains of IMR 4320 with 75 grain BT hornady cci primer in a fedral case.

Where do I start from, where do I look first?

Regards

Mark

Make sure you have at least a calibre of bullet seated in the case (0.243") load a 4 round group at that depth and then if the group is not as good as you would like seat the next 4 rounds 0.015" deeper keep doing this and the gorups should close up and then open up again keep the powder charge the same though.
 
Do you have a .308 FL sizing die handy? Remove the decapping pin and expander ball, and resize your .243 cases. This will size the body and outer part of the shoulder, but leave a "datum ring" that will help to align the cartridge in the chamber. Now neck size with a regular .243 neck sizing die, cap, charge and seat a bullet. Laborious, I know, but it is one way around a large chamber, especially if there is some eccentricity in it. Plan B is the set the barrel back 1/2" and have it rechambered.
 
Ok, A week or two ago I put a post up about tight cases when closing the bolt of my 243. I had some great groups but the case was not right so I have turned the sizer very slightly to push the shoulders back a little and this has helped the cases fit and they fit well. The new problem is that the groups are now shocking, can't get any better than 2 inch. Have tried bringing the powder charge up from the low end 37.7 again upto 41.5 The best being 39 grains which was where i was to begin with, which are still the best , but still crap.

I am loading 39 grains of IMR 4320 with 75 grain BT hornady cci primer in a fedral case.

Where do I start from, where do I look first?

Regards

Mark
Mark.
You don't say how much you stepped the powder up by? I generally step up 0.4 grains and then once I have a likely weight try it again and try +-0.2 grains as well.
You don't say what your seating is. The suggestion above of 10 thou off the lands is a good one for a starting seating. However these lighter bullets may not get that near and 50-150 thou range might be where you end up. Once you get a powder weight that's working, tweak the seating by no more than 4 thou at a time.
I am not a fan of Federal brass for reloading and suggest you get a box of Lapua brass and start afresh with that.
Going by the Hornady book, IMR 4320 is listed, but all your loads are over the maximum of 38.8 grains, so I think you need to look at that issue.
I also think you need to look at the resizing that you have been doing. Have you measured how much you have bumped the shoulders back? I suspect you may have bumped them back a bit far?
You've not mentioned trim length, but the trim lengths need to be to spec and the cases deburred.
Given the range of issues here, I think you need to find someone local that you can talk to on reloading on a regular basis and look over your shoulder. Also, you need to update your reloading book on what you are doing, both for brass prep and for actual loading.

One final thought, has something come loose on the rifle? How is it shooting its preferred factory ammo? It can take years to work through issues like these, so take your time and write down what you do.
Good luck. JCS
 
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Mark.
You don't say how much you stepped the powder up by? I generally step up 0.4 grains and then once I have a likely weight try it again and try +-0.2 grains as well.
You don't say what your seating is. The suggestion above of 10 thou off the lands is a good one for a starting seating. However these lighter bullets may not get that near and 50-150 thou range might be where you end up. Once you get a powder weight that's working, tweak the seating by no more than 4 thou at a time.
I am not a fan of Federal brass for reloading and suggest you get a box of Lapua brass and start afresh with that.
Going by the Hornady book, IMR 4320 is listed, but all your loads are over the maximum of 38.8 grains, so I think you need to look at that issue.
I also think you need to look at the resizing that you have been doing. Have you measured how much you have bumped the shoulders back? I suspect you may have bumped them back a bit far?
You've not mentioned trim length, but the trim lengths need to be to spec and the cases deburred.
Given the range of issues here, I think you need to find someone local that you can talk to on reloading on a regular basis and look over your shoulder. Also, you need to update your reloading book on what you are doing, both for brass prep and for actual loading.

One final thought, has something come loose on the rifle? How is it shooting its preferred factory ammo? It can take years to work through issues like these, so take your time and write down what you do.
Good luck. JCS

+ 1 with JCS, make sure you write down and label everything. nothing worse than working up a load your rifle likes, only to find you forgot to label that batch:doh::doh::doh:.
sinbad
 
mark im guessing that original problem with the bolt may have been excessive headspace


bring them round next week and lets put your rounds on to a runout gauge then we can see whats going on with your neck turning


some questions

what does a load rounded measure across the neck?
what thickness did you turn too?
are you using a neck bushing sizing die?
what bushing are you using?
 
Mark.
You don't say how much you stepped the powder up by? I generally step up 0.4 grains and then once I have a likely weight try it again and try +-0.2 grains as well.
You don't say what your seating is. The suggestion above of 10 thou off the lands is a good one for a starting seating. However these lighter bullets may not get that near and 50-150 thou range might be where you end up. Once you get a powder weight that's working, tweak the seating by no more than 4 thou at a time.
I am not a fan of Federal brass for reloading and suggest you get a box of Lapua brass and start afresh with that.
Going by the Hornady book, IMR 4320 is listed, but all your loads are over the maximum of 38.8 grains, so I think you need to look at that issue.
I also think you need to look at the resizing that you have been doing. Have you measured how much you have bumped the shoulders back? I suspect you may have bumped them back a bit far?
You've not mentioned trim length, but the trim lengths need to be to spec and the cases deburred.
Given the range of issues here, I think you need to find someone local that you can talk to on reloading on a regular basis and look over your shoulder. Also, you need to update your reloading book on what you are doing, both for brass prep and for actual loading.

One final thought, has something come loose on the rifle? How is it shooting its preferred factory ammo? It can take years to work through issues like these, so take your time and write down what you do.
Good luck. JCS

john mark is near me in norofolk i think we can sort betwean us hopefully
 
Reloading isn't that messy,as long as you have set up the neck or fl die correctly you shouldn't have a problem,I don't use a fancy competition die to shoot out to 1000yds,no stalking rifle needs that fancy kit :rolleyes:
 
Reloading isn't that messy,as long as you have set up the neck or fl die correctly you shouldn't have a problem,I don't use a fancy competition die to shoot out to 1000yds,no stalking rifle needs that fancy kit :rolleyes:

True that!
Don't chase your tail.
Back the load off and get some new brass and start anew.~Muir
 
well said ,swarovski, totally agree <I think sometimes people make it more complicated than it needs to be,as long as you go from a-z without missing anything out ,
 
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