Thread: Using comparator tool when seating projectiles.

Yeah,Nah. I got what you meant. But howdid you quote me? My daughter isn't here to help

bottom right of your post it says reply with quote under the like button

Duh, thank you

The Redding Instant Indicator is the solution that I use for producing constant CBTO ammo, it is set up using a known length dummy round. I seat all the projectiles between 4&5 thou too long with my Redding comp seating die and then run them through the instant indicator on a second press. This shows me how much I have to alter the comp die to seat the projectile to my desired depth. It is time consuming but makes for very accurate ammo.

Originally Posted by Tech

The Redding Instant Indicator is the solution that I use for producing constant CBTO ammo, it is set up using a known length dummy round. I seat all the projectiles between 4&5 thou too long with my Redding comp seating die and then run them through the instant indicator on a second press. This shows me how much I have to alter the comp die to seat the projectile to my desired depth. It is time consuming but makes for very accurate ammo.

I can see how that would work. I am going to do the same but use the comparator instead. My issue is I have a lot of Corelocts that I want to use for range shooting. Sometimes they shoot extremely well, sometimes not so much. On the face of it an identical load. COAL varies by up to 10 to 15 though. I'm going to choose a CBTO that's relevant and test. I don't want to waste my limited supply of BT's and AB's.

I struggled with inconsistencies in seating depth for a long time, was having about the same 10thou variance. The biggest improvement I got was annealing my brass regularly. It instantly dropped the range down to about 2-3thou. If you have access to one then I can’t recommend it enough, good for your brass life too.

Perhaps someone can point out the error of my ways?

I bought a Hornady OAL comparator set, and the Rod to measure projectile’s position agains the lands.
Watched YouTube to see how to do it.
I’m sure I did everything right, but when I loaded a bullet the bolt wouldn’t close, had to seat down, right back to my original OAL.

Originally Posted by Lauries Hut

Perhaps someone can point out the error of my ways?

I bought a Hornady OAL comparator set, and the Rod to measure projectile’s position agains the lands.
Watched YouTube to see how to do it.
I’m sure I did everything right, but when I loaded a bullet the bolt wouldn’t close, had to seat down, right back to my original OAL.

I'll bet the projectile is getting stuck in the lands and giving a false measurement.
Lookup ultimate reloader on youtube measuring the lands he shows a good method without having to use the hornady tool just with a fired case and some loktite.
I had similar issues with the hornady tool and have used the loktite method ever since.

Personally i wouldnt worry about trying to measure to the lands with a Hornady OAL tool, I have always just loaded a projectile long in an empty case, tried it in the rifle with a bit of vivid on the ogive and just progressively seated it deeper in the case and kept trying it in the rifle till the bolt finally closes nicely & faint mark of rifling on the vivid. Measured that BTO then knocked it back another 10 thou and started from there. At the end of the day you had a load that was working well in that gun most of the time with the issue being inconsistent seating depth due to measuring COAL rather than BTO. I would load a round at your original powder charge and COAL, use Hornady Item #B234 Comparator set to measure what that ends up being as a BTO measurement. Once you have that measurement, Load up a seating depth ladder close to what that measurement is, for instance if it measures 2.610 BTO, i would load a ladder 3 rounds at each depth from 2.619 down to 2.601 in 3 thou increments & go shoot them, Giving you a 18 thou spread in seating depth around the area that worked for you before. Surely somewhere in there you will find what works.

Originally Posted by dannyb

I'll bet the projectile is getting stuck in the lands and giving a false measurement.
Lookup ultimate reloader on youtube measuring the lands he shows a good method without having to use the hornady tool just with a fired case and some loktite.
I had similar issues with the hornady tool and have used the loktite method ever since.

I also recommend the Loctite method , simple and effective.
It’s the very first thing I do when working with a new rifle/projectile combination.
In my experience there are very few factory rifles that when a round is loaded to maximum magazine length the projectile is anywhere near the lands .
After I have determined that I’m not dealing with one of those unicorns ( the Loctite method) I just load a selection of 5x powder charges at maximum magazine length .
When I am happy with my chosen powder charge I then load a selection of 5x rounds in decreasing seating depths to see if I can find a depth that shows promise .
When that is found I load up at least 20x rounds to confirm that depth wasn’t a false flag and that it is consistent.

Originally Posted by 7mmsaum

Use cotton buds to wipe graphite powder on the inside of case necks and on projectiles

Fingers stay clean then

I just dip the neck in

Do any of the seating dies actually seat on the ogive of the bullet, I have Lee (the higher end) and Hornady custom grade dies, and these all seat not on the tip but not very far up the bullet, certainly nowhere near the ogive where my comparator touches the bullet.

My way of thinking is you cannot get consistent seating depth unless your seating die and comparator are contacting at the same place, and ideally this should be at the same place as your lands would touch the bullet. I have thought about making my own seating insert, do the Redding dies or any others contact the bullet closer to ogive?

your looking at it wrong..... the seating die seats all projectiles by the bit of the olgive/curved front half at the same fatness area for want of better term...it will be at same fatness reguardless of projectile shape even a round nose but of course that will be really close to tip...with my 170grn rn in .270 I need to back the die well out to seat projectile as cant lift seater stem high enough.

For example, my 6mm dies after seating the bullet leave a small ring around the bullet, the bullet is only 4.5mm in diameter at this point.

Wouldn't it make more sense for the seating die to sit at say 6mm or 5.8mm. This way there is less room for bullet variances upsetting consistent seating depth, as it is the distance from the case base to where the bullet is going to meet the lands we are trying to keep the same.

If the bullet has a slightly different shaped curve Infront of the ogive it then wouldn't matter as the ogive would be seated to the same spec each time.

far more chance of it jamming that close to outside...and the olgive is the whole curve or the bit at calibre size??? back to OPS question, it doesnt matter where it touches as long as its the same each time..in my rifles I seat using the same one round to set up diesfor just about all projectiles other than round nose... they just go mag length and it works.