S/B FL Resizing & Neck Tension?

G19Kev

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New to reloading, and I need help about this subject. I have an AR-10 6.5cm I want to precise handload for, and I've read you want to use a small base die to size with. I think RCBS makes the only one, but it isn't a bushing die, at least I don't think so. You can correct me if I'm wrong, and that would answer my question. Assuming I'm right, how do you impose a desired neck tension when you go to seat the bullet, while utilizing a small base sizing die?
 
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Bradv86

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You could remove the expander ball and perform that operation separately using an expander mandrel of the desired size.

While I don't have any experience with a 308 in an auto, I have not needed a small base die for 223 or my 260 Rem gasser. YMMV.
 

Bullspotter

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I guess it depends on how tight your chamber is as far as the Small base die is concerned, Like bradv86 suggested, take out the ball and then go at it with the mandrel of your choice. I have not needed a small base die for any of my auto loaders, 2 260s, 1 308, 1 6 Cm and several 223s. I see no need to go to a SBD unless it is needed?????
 

918v

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Why is everyone worried about the need? It’s only .001-.002” smaller than a regular die. It means nothing in terms of case life. Nothing.
 

G19Kev

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Why is everyone worried about the need? It’s only .001-.002” smaller than a regular die. It means nothing in terms of case life. Nothing.
It's for increase cycling reliability in a semi-auto...
 

G19Kev

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You could remove the expander ball and perform that operation separately using an expander mandrel of the desired size.

While I don't have any experience with a 308 in an auto, I have not needed a small base die for 223 or my 260 Rem gasser. YMMV.

I guess it depends on how tight your chamber is as far as the Small base die is concerned, Like bradv86 suggested, take out the ball and then go at it with the mandrel of your choice. I have not needed a small base die for any of my auto loaders, 2 260s, 1 308, 1 6 Cm and several 223s. I see no need to go to a SBD unless it is needed?????
Well, I guess I'll just go with a regular full length bushing die. Hard to tell what to take seriously when coming across what you read.
 

MtnCreek

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Why do you want a bushing die for this?

Dillon carbide is a good die for one pass sizing and is small base.
 

G19Kev

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Why do you want a bushing die for this?

Dillon carbide is a good die for one pass sizing and is small base.
I'm finding out that "small base" is more of a marketing ploy, rather than an actual distinguished difference from a regular full length die... So, maybe I don't need to bother with that. However, I want a bushing die, so I can make a custom neck tension, both for bullet security in a semi-auto without having to crimp, and potentially more consistent muzzle velocities...
 

Dthomas3523

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    You just don't get it, do you?

    He’s saying it won’t hurt to use the small base die. And since you don’t have dies, you can buy that and not take chance of needing to buy it after a non small base possibly doesn’t work.
     

    Dthomas3523

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    I'm finding out that "small base" is more of a marketing ploy, rather than an actual distinguished difference from a regular full length die... So, maybe I don't need to bother with that. However, I want a bushing die, so I can make a custom neck tension, both for bullet security in a semi-auto without having to crimp, and potentially more consistent muzzle velocities...

    It’s not a ploy. There are several valid reasons a small base is required.

    But using one when not required won’t hurt you.
     

    MtnCreek

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    I'm finding out that "small base" is more of a marketing ploy, rather than an actual distinguished difference from a regular full length die... So, maybe I don't need to bother with that. However, I want a bushing die, so I can make a custom neck tension, both for bullet security in a semi-auto without having to crimp, and potentially more consistent muzzle velocities...
    I'm not sure about it being a marketing ploy. But one standard die may size just as much as another SB... tolerances.

    I just noticed this is creedmoor. Disregard what I said about dillon carbide; I was thinking 308.

    I'd still skip the bushing for this. JMHO.
     
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    Bradv86

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    I'm finding out that "small base" is more of a marketing ploy, rather than an actual distinguished difference from a regular full length die... So, maybe I don't need to bother with that. However, I want a bushing die, so I can make a custom neck tension, both for bullet security in a semi-auto without having to crimp, and potentially more consistent muzzle velocities...

    The mandrel is still a viable option. You can have your cake and eat it too here, as long as you are willing to split the sizing and expanding steps apart.

    Additionally the mandrel will find use in many more loads, not just expanding a small base die that doesn't have a bushing option. If you are getting into precision you will wind up here eventually anyway.
     
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    nn8734

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    I'm finding out that "small base" is more of a marketing ploy, rather than an actual distinguished difference from a regular full length die... So, maybe I don't need to bother with that. However, I want a bushing die, so I can make a custom neck tension, both for bullet security in a semi-auto without having to crimp, and potentially more consistent muzzle velocities...
    Not a “marketing ploy” as the cost of a small base die set is the same as a standard die set. While they aren’t often required, those with very tight match chambers may require that extra.001-.002 extra sizing at the base to ensure reliable feeding (either manually or auto-load) into the chamber without getting bound up at the base (hence the term “small <outside diameter> base”).

    I use one for my Mk12’s Douglas SPR barrel as I was experiencing failures to feed occasionally with the standard 5.56 die I was using at the time.
     
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    G19Kev

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    Uhhh, no he gets it. In this case you didn’t.

    To repeat what others that do get it stated:
    Go with the SB die in case you “might” need it.
    Forget the bushing, use the mandrel.
    Now I'm going to go bushing for sure, just to piss you, and your friend off... To repeat what others said, that didn't say, what you said they said: "They haven't needed a s/b die." If I can get away with a regular full length die, which is what others have brought to light here, and use a bushing to get the neck tension I want, which is customizable by the thousandth of an inch, not just caliber specific, and in one operation, why would I go the mandrel way, if I don't have to? It's a good back up suggestion, why y'all are being so aggressively suggestive about it, is what I don't get...
     
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    Bradv86

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    Now I'm going to go bushing for sure, just to piss you, and your friend off... To repeat what others said, that didn't say, what you said they said: "They haven't needed a s/b die." If I can get away with a regular full length die, which is what others have brought to light here, and use a bushing to get the neck tension I want, which is customizable by the thousandth of an inch, not just caliber specific, and in one operation, why would I go the mandrel way, if I don't have to? It's a good back up suggestion, why y'all are being so aggressively suggestive about it, is what I don't get...

    Because you are on a board for precision rifle shooting, asking about precision reloading. A huge number of people here are combining mandrel and bushing even. No one is here blowing smoke up your ass, they are literally answering your question to what is considered best practice by many people, be it a gas gun or bolt.
     

    G19Kev

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    Because you are on a board for precision rifle shooting, asking about precision reloading. A huge number of people here are combining mandrel and bushing even. No one is here blowing smoke up your ass, they are literally answering your question to what is considered best practice by many people, be it a gas gun or bolt.
    So it's an equal practice to use a body die followed with a expander die with a madrel, vs a full body bushing die?
     

    Dthomas3523

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    So it's an equal practice to use a body die followed with a expander die with a madrel, vs a full body bushing die?

    No, you use the bushing die and a mandrel.

    A bushing will more or less uniforms the outside of the neck and push the imperfections to the inside. Which is counterproductive.

    So, you use a bushing or non bushing die to size the neck down, then a mandrel to expand it. Which uniforms the inside of the neck which is where the bullet will he touching. Also, mandrels are available in .0005” increments.

    Using a mandrel to finalize your inside neck diameter has been proven repeatedly to provide better performance on paper and chronograph.

    Then the question is why not just use a non bushing die. The bushing die allows you to only size the neck down the minimal amount needed for your particular neck. Especially if you neck turn.

    People are seeming so aggressive because you’re asking for advice, but then immediately telling people why they are wrong. That won’t make you any friends. Especially when you clearly don’t understand what’s going on (which is fine, everyone starts somewhere, but act as such).
     

    Cascade Hemi

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    New to reloading, and I need help about this subject. I have an AR-10 6.5cm I want to precise handload for, and I've read you want to use a small base die to size with.
    You've read wrong. Small base dies are a waste of time and money. Take the advice given to you and buy regular dies.
     

    G19Kev

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    No, you use the bushing die and a mandrel.

    A bushing will more or less uniforms the outside of the neck and push the imperfections to the inside. Which is counterproductive.

    So, you use a bushing or non bushing die to size the neck down, then a mandrel to expand it. Which uniforms the inside of the neck which is where the bullet will he touching. Also, mandrels are available in .0005” increments.

    Using a mandrel to finalize your inside neck diameter has been proven repeatedly to provide better performance on paper and chronograph.

    Then the question is why not just use a non bushing die. The bushing die allows you to only size the neck down the minimal amount needed for your particular neck. Especially if you neck turn.

    People are seeming so aggressive because you’re asking for advice, but then immediately telling people why they are wrong. That won’t make you any friends. Especially when you clearly don’t understand what’s going on (which is fine, everyone starts somewhere, but act as such).
    Whaaaat? Somebody makes mandrels in .0005" increments??... B.S.! What the hell do y'all talk each other into on here?? It's physically impossible to control diameters in that capacity upon expansion...
     
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    spife7980

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    Whaaaat? Somebody makes mandrels in .0005" increments??... B.S.! What the hell do y'all talk each other into on here?? It's physically impossible to control diameters in that capacity upon expansion...
    CF670E50-0716-4210-A9F8-627ECA0C03E8.jpeg
     
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    Bradv86

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    They even make weight plates in 2.5lb increments so once benching 275 becomes easy you can go to 280 after you are done working concrete for the day.
     
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    smoothy8500

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    Based on the OP's other posts it appears they are a newbie to reloading and shooting and just needs to start at the basics and learn to crawl before running....