Sinclair Expander Mandrel Die Test

So if I gather correctly, the majority of the runout is occuring during the seating process. Have you considered using a competition style seating die that aligns things better? I would be curious as to how much it helps.

FWIW I have a Forster mic seating die, and runout is never more than .002" on bullets seated with that. I get .005" occasionally with a standard redding seating die.
I have considered it. But I haven't really ever had an issue with this rifle not grouping or being consistent. Every little bit helps, so maybe one day I'll get a better seating die.
 
I gotta second the forster benchrest seater. They seem to be the best design I've tried so far for concentricity. Redding and Hornady seater's not as precise. Jud is one of the better reloaders and posters I've encountered on here and his posts have taught a lot, his mandrel compared to expander ball dies post has caused a lot of interest and discussion on a little talked about topic. I'm trying to shoot a three way test with different neck sizing techniques but the weather up here is discouraging to say the least.
 
There are a lot of ways to get the same result so not everything is set in stone. Those of us who us mandrels do it for the combination of inside neck expansion vs outside neck restriction, run out, and neck tension consistency. For example I like to turn all my necks down just enough to get rid of the neck thickness consistency issues but with this method I have good enough results to not have to turn necks. I full size using a bushing fl sizing die and decapper with no expander ball. I then mandrel expand the neck. So it takes 2 runs through a die to complete the sizing process. On neck turned brass the run out is less than non but not a lot. However, during seating with a competition floating head seater I still seat 1/3, rotate the case, seat 2/3, rotate and finish the seating. It's just a habit now. In doing direct comparisons of rotating vs not rotating, I have seen .003 difference. Rotating I expect .001 or less run out. With out rotating I expect .002-.005 and hope for the lesser. It is not enough to probably worry about. What I do see is lower es/sd with the mandrel vs bushing only as a whole. It seems getting under 10 sd is that hard with consistent process controlling neck tension.
 
I gotta second the forster benchrest seater. They seem to be the best design I've tried so far for concentricity. Redding and Hornady seater's not as precise. Jud is one of the better reloaders and posters I've encountered on here and his posts have taught a lot, his mandrel compared to expander ball dies post has caused a lot of interest and discussion on a little talked about topic. I'm trying to shoot a three way test with different neck sizing techniques but the weather up here is discouraging to say the least.
At the time when I bought the dies I have I was sticking to a budget. I am considering getting some Forster dies in the future. Thank you for the compliments. I try to do my best and share what works for me and what I find.
 
There are a lot of ways to get the same result so not everything is set in stone. Those of us who us mandrels do it for the combination of inside neck expansion vs outside neck restriction, run out, and neck tension consistency. For example I like to turn all my necks down just enough to get rid of the neck thickness consistency issues but with this method I have good enough results to not have to turn necks. I full size using a bushing fl sizing die and decapper with no expander ball. I then mandrel expand the neck. So it takes 2 runs through a die to complete the sizing process. On neck turned brass the run out is less than non but not a lot. However, during seating with a competition floating head seater I still seat 1/3, rotate the case, seat 2/3, rotate and finish the seating. It's just a habit now. In doing direct comparisons of rotating vs not rotating, I have seen .003 difference. Rotating I expect .001 or less run out. With out rotating I expect .002-.005 and hope for the lesser. It is not enough to probably worry about. What I do see is lower es/sd with the mandrel vs bushing only as a whole. It seems getting under 10 sd is that hard with consistent process controlling neck tension.
I have been able to get SDs under 5 by bushing FL sizing followed by mandrel expanding, without any neck turning. This is using Lapua brass. My runout with seated bullets is =<.002". The only thing I havent been able to achieve is 1/2 MOA groups on paper. Would neck turning help this at all? Its a factory chamber so there is a lot of clearance around the neck dia.
 
I have been able to get SDs under 5 by bushing FL sizing followed by mandrel expanding, without any neck turning. This is using Lapua brass. My runout with seated bullets is =<.002". The only thing I havent been able to achieve is 1/2 MOA groups on paper. Would neck turning help this at all? Its a factory chamber so there is a lot of clearance around the neck dia.
Honestly, I've shot 1/2 MOA groups with all of my rifles and this is the first time I've really experimented with a different method other than standard reloading dies. Every little bit helps, but in my opinion, a good barrel, good bedding, good scope, good reloading components, consistent powder charges, being in a velocity node, and tuning your seating depth are the biggest contributors to accuracy in my experience. You can have a Savage Axis with a Tasco and load with $5000 worth of reloading equipment and doing every possible step chasing 1/2 MOA. Or you can have a good shooting factory rifle or a custom rifle and use quality bullets, brass, powder, primers, with good reloading equipment and you'll get good results. Neck turning your brass isn't going to show much on paper if you're out of node and haven't tuned your seating depth. It also doesn't help if your powder charges aren't on the money.

With that being said, I would focus on testing your seating depth and tinkering with your bullets. Everything you are doing and the consistency of your ammo proves you have good components, good equipment, and a good load.
 
I have been able to get SDs under 5 by bushing FL sizing followed by mandrel expanding, without any neck turning. This is using Lapua brass. My runout with seated bullets is =<.002". The only thing I havent been able to achieve is 1/2 MOA groups on paper. Would neck turning help this at all? Its a factory chamber so there is a lot of clearance around the neck dia.
Not really. If you had really bad run out it'd be a consideration but you don't. I would prolly focus on seating depth with those results. Have you down that? Multiple bullets choices?
 
Not really. If you had really bad run out it'd be a consideration but you don't. I would prolly focus on seating depth with those results. Have you down that? Multiple bullets choices?
I have focused on 1 bullet, the 143eldx. Have loaded and tested 225 rounds trying to tune in. Best I can get consistently is .75 MOA with a few small er groups now and then. I have tried seating depths from .005 to .090 jump, and every .005 in between. Seems to do best around .040. I actually just recieved my order of 3 new bullets to try, a 142 ABLR, 140 ELDm, and 140 berger elite hunter. I figure Ill get one of them to shoot tighter. Should I tune seating depth first or powder charge 1st? I have always done powder charge 1st in the past, but Im questioning if thats the best approach?
 
I have focused on 1 bullet, the 143eldx. Have loaded and tested 225 rounds trying to tune in. Best I can get consistently is .75 MOA with a few small er groups now and then. I have tried seating depths from .005 to .090 jump, and every .005 in between. Seems to do best around .040. I actually just recieved my order of 3 new bullets to try, a 142 ABLR, 140 ELDm, and 140 berger elite hunter. I figure Ill get one of them to shoot tighter. Should I tune seating depth first or powder charge 1st? I have always done powder charge 1st in the past, but Im questioning if thats the best approach?
I do charge at 20 thou with eld's. What powder and primer?
 
Few questions. All the mandrels I have seen come in two sizes, expander and turning. How do you control neck tension? Bushings come in sizes every .001. If there are other mandrels available what is the process for determining the correct mandrel? I want to try this method.

Thanks Dave
 
Few questions. All the mandrels I have seen come in two sizes, expander and turning. How do you control neck tension? Bushings come in sizes every .001. If there are other mandrels available what is the process for determining the correct mandrel? I want to try this method.

Thanks Dave
The mandrels come in .001 and .002 smaller than bullet diameter. This gives you the option of .001 or .002 of neck tension. You'll also get a little spring back so add an additional .0005 or so to the above numbers. So you have a choice between 0.0015 or 0.0025 neck tension. If you want more or less, 21st century sells their mandrels in 0.0005 increments I believe.
 
Honestly, I've shot 1/2 MOA groups with all of my rifles and this is the first time I've really experimented with a different method other than standard reloading dies. Every little bit helps, but in my opinion, a good barrel, good bedding, good scope, good reloading components, consistent powder charges, being in a velocity node, and tuning your seating depth are the biggest contributors to accuracy in my experience. You can have a Savage Axis with a Tasco and load with $5000 worth of reloading equipment and doing every possible step chasing 1/2 MOA. Or you can have a good shooting factory rifle or a custom rifle and use quality bullets, brass, powder, primers, with good reloading equipment and you'll get good results. Neck turning your brass isn't going to show much on paper if you're out of node and haven't tuned your seating depth. It also doesn't help if your powder charges aren't on the money.

With that being said, I would focus on testing your seating depth and tinkering with your bullets. Everything you are doing and the consistency of your ammo proves you have good components, good equipment, and a good load.
was going to answer when I read this, already what I would of said. I don't neck turn at all, only thing I haven't gotten into in reloading so far. Don't have a gun/load that isn't four's or better, I'm sure I'll try it sometime.

Juds suggestion about making sure gun is capable of good accuracy and then doing load work-up with special attention to distance off lands tuning and powder charge tuning. Also maybe try several bullets to see if the rifle may like a certain one. Good luck and good shooting. Dave
 
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