small base sizer dies

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Mitchell

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One of my dad's friends said that i should be using a certain sizing die for my BLR. Should i be using a different full length sizing die? what is this die called and what does it do differently from a normal full length sizing die?
thanks, mitchell
 
BLR's don't normally require a small base die. They do require reasonable loading practices though. If one persists in loading maximum loads you may experience hard extraction one day, and then find even with lighter loads it will be hard to extract a fired shell. This is because heavy loads or overloads can cause the camming open areas within the bolt to set back. It is an expensive repair.

Small base dies are normally used when reloading ammunition that has been fired in various rifles including semi-automatics and the base may need this smaller sizing so it will fit in a semi-auto and let the bolt close easily.
 
i reload for two blr's and have never needed a small base die. i don't exceed max loads from the manuel. i use a batch of brass only in the blr and never mix with brass fired in other rifles.
 
I tried some of my reloads to see how they functioned in my BLR (.243 win) and it seems like they don't chamber very nicely compared to the factory shells i got. Am i resizing wrong? I screw the full length sizing die in till it touches the shell holder then screw it in another quarter to a half a turn more. Is there a special method for .243? I'm using my brass that i fired from this gun.
 
Mitchell said:
I tried some of my reloads to see how they functioned in my BLR (.243 win) and it seems like they don't chamber very nicely compared to the factory shells i got. Am i resizing wrong? I screw the full length sizing die in till it touches the shell holder then screw it in another quarter to a half a turn more. Is there a special method for .243? I'm using my brass that i fired from this gun.
Click to expand...

First try a fired case and see how it goes back in the chamber and what it feels like.

Then take that same case and resize it and try it again. If it is harder to close the action, it needs a bit more sizing.

You may have to remove a few thou from the bottom of the die and set it down more, or use more lubrication or get a press that does not spring as much. There are a lot of variables.

If the empty sized case goes in and the action closes easily, but when you load the round and try it, it does not close easily, you probably have the seating die body set too low in your press or your brass may need trimming...

There are a lot of variables.

.​
 
have you checked overall lenth? i load for a 308 and 358. also owned 243 before and never had problems. if your lenth is to long the bullet might be contacting the rifling. have you fired any of these reloads. any pressure signs.it sounds like your setting the die for full lenth sizing. have you used the dies for another rifle before. was it all good? do you have another 243 to try those loads in? is it hard to close the lever. i have heard in rare cases small base dies are required. lots of things to check out.
 
My blr works fine with just a neck size for a couple of firings and then a full length sizing. You have to watch your headspace if you are bringing the shell holder in contact with the die. Blacken a resized case and try to chamber it to see where it is tight. What type of dies are you using?
 
I am using lee dies and these are brand new and the BLR is the only .243 i have. I am setting my FL sizing die just as it says in the instrustions that came with the press.
 
When i go and fire these what do i look for to see if there is high pressures?
257Roberts, can you explain to me what you mean by watch out for my headspace? becasue when i loaded these i did make contact with the shell holder on the die.
 
even though you set your dies up correct...this i learned the hard way:redface: make sure when sizing you go through the full stroke..dont stop once the primmer falls out...make sure your dies hits the same depth you set it all up for..eye ball them all till you get the feel of it
 
Hi Mitchel, Your headspace is the distance from the case head to the shoulder of your case. if you move the shoulder of your fired case back when resizing you end up with to much headspace and your cases will stretch during firing and may seperate above the case head. If your die is set properly you should only touch the shoulder of your fired case and not move the shoulder back as this will create a headspace problem. I have found with my 243's that when you size a fired case the shoulder does move fwd and would have to be pushed back to chamber in the rifle. It all has to be done with Die adjustment. If you blacken an unloaded, resized case above the flame of a candle and try to chamber it you will see where contact is being made in the chamber and that will help you to adjust for your problem. If your case needs to be resized more or the shoulder needs to be set back more remove some material from the top of your shellholder not the die. Easier and cheaper to replace and then only use that shell holder for resizing that ammo. Next you should explain your bullet seating steps, this could also create problems with chambering reloads. I do not have any problems with my lee dies and most of them I can set so the shell holder does contact the die. I will send a PM with info on pressure sighns.
 
Mitchell said:
When i go and fire these what do i look for to see if there is high pressures?
257Roberts, can you explain to me what you mean by watch out for my headspace? becasue when i loaded these i did make contact with the shell holder on the die.
Click to expand...

The first indication of excessive pressure may be primers that appear quite flat. That is not reliable because headspace can also cause that. If the bolt is harder to open that is the first sign that the load it too hot.

I think concerning a rimless case the easiest way is to think of headspace as the distance between the rear of the case when it is fully forward in the chamber, and the bolt face of a closed bolt... and this is exactly where you do not any space or at best only a thousands of an inch.

For instance if a rifle has .005" (5 thou) headspace, that is how much space there is between the rear of the case and the fully closed bolt face, when the case is fully forward in the chamber.

What happens on firing is the firing pin will drive the case forward until it stops on the shoulder and the primer ignites the powder. Very quickly as the pressure develops, the thinner case walls expand and stick against the chamber walls... as the pressure builds more, the rear of the case where the brass gets thicker just ahead of the web will stretch back until the case head is stopped by the bolt face. There will be a small area inside the case now that is weaker and that case now fits that chamber perfectly. If you push the shoulder back again on this case when resizing it, you will create headspace again with that case and the same procedure as above will occur on firing.. the case will stretch more and this time possibly separate... separations will occur eventually and they can do damage to the rifle and the shooter.

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Mitchell said:
One of my dad's friends said that i should be using a certain sizing die for my BLR. Should i be using a different full length sizing die? what is this die called and what does it do differently from a normal full length sizing die?
thanks, mitchell
Click to expand...
Demand for these dies was so great when the BLR came out that RCBS came out with a series of sizers for the Brownings such as 300win mag BLR. Now they have the small base size dies in calibers for all autoloaders. Some bolt action shooters also use then to insure feeding under extreme conditions as do some slide gun and lever gun operators.

Obviously brass life is not a consideration to these people who have maybe spent big bucks and devoted a lot of preparation for that hunt in some distant place.

Why are they used? Hey most everybody has their own way of doing things so if these dies give a guy a mental edge, why not!

The tool makers are happy to cater to demand. For example 357mag dies when 38spl will work, 44 mag dies when 44spl will work and then there are the so called bench rest dies which are made to the same industry standards as regular dies..
 
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