Seating Die Help

[King31]

After reloading during the rain on Sunday I finally had the time to crank out some rounds. Being a cautious newbie I ended up measuring OAL on several of those completed rounds. I had some concerning numbers ranging from 1.121 to 1.130. I was shooting for 1.125 per several sources. Does anyone have any advice as to why this number is changing so much? My bench needs more support (in the process) as I think perhaps it was jarring the press slightly. It is a Dillon RL550B with Lee deluxe carbide dies w/ Dillon lock rings. Any advice would be greatly appreciated!

 

[sugarcreekbrass]

I just recently asked the same question here (look up: Rainier 124 gr HP). I think the thread is on page 2 right now. I know your bench should be solid but not experienced enough to know how much effect it will have on seating bullets. The guys who helped me said it is common for there to be a variance and no need to worry.

 

[indyjohn]

Those numbers are an acceptable variance, generally speaking. They will go bang out of your firearm just fine, provided you've put the proper amount of powder in them. Will they group a ragged hole on a paper target? Maybe. In the 15 years I've reloaded for competition, I've come to accept a variance of .01 because of the press I use and the components I buy.

Can you improve that? Yes. Will it make a difference? That depends on your marksmanship capabilities behind the trigger.

Edit: Can you get to .005 (1.123 - 1.128)? Yes, but it takes more detailed case prep and technique on how much pressure you apply on the press handle. And a high end die set.

 

[Sling10mm]

Like John said, I would find this variance acceptable as well….. you are within 1.125+/-.005. The differences might be in the bullet shape. Not sure what bullet profile you are using, but if they are round nose, I could see that much variance. When I do hollow point or flat nose, I can usually keep it within +/-.001 or .002.

 

[Deadeye(+)]

Agreed with the above. It's a fair tolerance. Definitely could be bullet shape. I've loaded HP .223 with weird numbers and looking closely the tips were kind of odd as in slanted points. But yours sound very close to where they need to be

 

[noylj]

There is cautious and there is being over-cautious. Did your manuals tell you that COL needed to be controlled tighter than you are getting? If it was that critical, it would be written up in large type warnings. COL concerns are in the 0.1" range (the initial concern was when a 9x19 load at about 33000psi had the bullet set-back 0.25" and produced about 60000 psi). Most control COL to 0.01". You are at about 0.005". You just can't get much better than that. If curious, measure some factory ammo and also consider that bullets from different swaging dies will have some variation in ogive and meplat and, if you inspect all your bullets, you'll notice some variation in the box (just as bullet molds vary as the cherry wears or is replaced).

 

[Broom_jm]

One thing to keep in mind is you're measuring your rounds from base to the tip of the bullet, which can definitely vary by the amount you are seeing. However, the tip of your bullet is not what contacts the barrel first, when you fire off a round...the ogive is. If you were to measure from the base of the brass to the ogive, you would probably find an even tighter tolerance, which is to say plenty for the work you're doing.

 

[indyjohn]

One thing to keep in mind is you're measuring your rounds from base to the tip of the bullet, which can definitely vary by the amount you are seeing. However, the tip of your bullet is not what contacts the barrel first, when you fire off a round...the ogive is. If you were to measure from the base of the brass to the ogive, you would probably find an even tighter tolerance, which is to say plenty for the work you're doing.

This is quite true.

I have one of these for each of my rifle calibers: http://www.sinclairintl.com/reloadi...n-mic-cartridge-headspace-tool-prod33476.aspx

I have one of these for each of my pistol calibers: L. E. WILSON Inc.

 

[billybob44]

Be sure to "Full Cycle" it..

After reloading during the rain on Sunday I finally had the time to crank out some rounds. Being a cautious newbie I ended up measuring OAL on several of those completed rounds. I had some concerning numbers ranging from 1.121 to 1.130. I was shooting for 1.125 per several sources. Does anyone have any advice as to why this number is changing so much? My bench needs more support (in the process) as I think perhaps it was jarring the press slightly. It is a Dillon RL550B with Lee deluxe carbide dies w/ Dillon lock rings. Any advice would be greatly appreciated!

The first thing that comes to mind is that you may not be going through full cycle each time, due to loose mounting??

I use a RL550 with Dillon Dies, and I can get 1.125" +/- .001" on most all of my 9MM 115gr.+124gr. loads.

Also be sure to set your seat depth while you have an unsized case in the size die position. If you set your seat depth with no case in the size die position, your OAL will be different when your operating your press with all stations filled..Bill.

PS: As said upthread, you may?? have better luck with a better quality die set??.....

 

[Electronrider]

Depending on how bad your reloading OCD is, you could measure all the produced ammo, and group them by length. then go shoot the various lots off of a rest and see if it makes a diference. Bonus OCD points for chrono all of them to see if that .005 makes a difference. Like others have said, it appears to be a non issue, but people who are very picky tend to want to see for themselves. That would tell you for certain if it is making a noticable difference.

Choot 'em!

 

[U.S. Patriot]

The most accurate means is to measure to the ogive. That's where the plunger in the seating die makes contact. Not to the tip of the bullet as measuring with calipers. Since no two bullets are going to be the same length from base to tip, your COAL will very. I normally see anywhere from +.003-.005 on my pistol rounds.

 

[straight-shooter]

Bullet nose shape and where it contacts the seating die will vary the seating depths. Not all bullets in a batch have and exact thickness or shape to make it ultra consistant. As said earlier, if you measure from the ogive and not the bullet tip your measurements will be more consistant.

 

[King31]

Thanks everyone for the replies. Being cautious can never hurt, but now I'm reassured that it most likely isn't a problem. I have a Dillon case gage that the majority of my produced rounds go through as well. Luckily my father beefed up my bench this week with a couple oak 2x10s, so hopefully it will be stout now!