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Posted: 3/1/2010 6:20:13 PM EDT
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I'd like to start reloading for .303, and the guy at the store told me that I don't need neck-sizing dies.
He said that I could use full length dies and just "turn back" the resizing die until it resizes the case just enough to fit into the chamber. Does this make any sense? The case already fits in the chamber without any resizing... Should I avoid full length dies? Thanks. |
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Well the british made loose and shitty wartime chambers....on purpose. They wanted the round to chamber with dirt and grime. A lot of them were wide too. You are probably better off to leave them blown out to the chamber wall and only neck sizing. Only when you have trouble chambering due to the shoulder being blown forward will you need the FL die. If you partial size you'll be squeezing the side of the brass. This will overwork your brass.
I learned this the hard way partial sizing myself. If your chamber is straight and not banana shaped or your neck not off center from the cartridge body it'll work. If you have one of these two problems then you're stuck FL sizing. If you have a commercial chamber you're probably fine partial sizing. |
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Thanks for the reply.
So if I get full length resizing dies, and my chamber is straight, can I just run the expander ball through the neck and be done with it (assuming the case still chambers)? I've only reloaded for semi-autos before, so I've never partially sized. |
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There has been recent talks over at subguns.com' reloading forum about 303... concensus is that OE surplus chambers can be long or short, thus they suggest setting die to size the case just enough to allow for slight snug feel when closing bolt.
If you FL size the case, and the rifle has a long chamber, the case will blow out (fire form to the chamber), then you is going to work it back to the tiny dimension, then blow it out again,,,, case life going to be rather short... size just enough to fit chamber. Hopefully Subguns will allow link from AR15: 303 more 303 |
| I know what you are asking and it is called partial resizing. Yes it does work if you take the time to make sure that the worst cases fit your chamber. In fact one of the ballisticians at Sierra several years ago recommended it over neck sizing because it tends to align the entire case with itself. |
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Quoted:
Thanks for the reply. So if I get full length resizing dies, and my chamber is straight, can I just run the expander ball through the neck and be done with it (assuming the case still chambers)? I've only reloaded for semi-autos before, so I've never partially sized. It will take just a little more than just running the expander ball in & out of the case. The case neck must be sized down & then expanded out to properly hold a bullet. A quick run down on the process. Remove the striker/cocking peice from your bolt to eliminate the resistance of the cock on closing feature, On an empty chamber, close the bolt a few times to feel how it closes with no resistance, (Just for a base line comparison) Take two peices of brass that are fire formed to the chamber in question and make sure they are trimmed to the proper length BUT NOT SIZED, Insert one trimmed/unsized/unlubed/fired cartridge from that rifle onto the bolt and gently chamber it, feeling how tight it is (there should be some resistance when chambering the fire formed brass), Go to your press, run the ram all the way up, place a nickle on it and adjust your die down until the die body is touching the nickle. (at this point, the die is set for neck sizing only)(the reason for the nickle thick space is that unless your rifle is seriously messed up, the die should be set to a headspace longer than your chamber or even field, i.e., neck sizing only) Remove the nickle, size only one your lubed brass, remove the lube, insert the dry brass onto your bolt and test the chamber fit again, comparing it to the unsized one, (remember, do not size both peices of brass, the unsized one is for comparison) If the brass feels the same as it did when unsized (it should), adjust your die 1/16 turn down and size the brass again. Repeat the fit test & 1/16 turn down process until you can feel that the bolt is slightly easier to close than on an unsized brass but not as easy as on an empty chamber. Adjust your die down an additional 1/32 of a turn and set the lock rings. Your die is now set to size the brass specifically for that chamber to feed with minimal resistance without over working the brass (partial sizing). The only down side to this process is that your loaded ammo may not function in any other or most rifles for the same cartridge. MLG |
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I load for three Lee Enfields, and this is what I've found to be the best combination of loading dies; the Lee set that contains the normal FL die, their collet neck sizing die, and their bullet seater. If you own more than one Lee Enfield, segregate your brass by the rifle it's fired in. Normally, you will use the collet die to neck size only. This will minimize work-hardening of your brass, and will hopefully increase case life.
What has essentially happened is that you have changed how the rifle headspaces, changing it from headspacing on the case rim, to headspacing on the case shoulder, just like any rimless case design. Case rim thickness varies tremendously from brand to brand of brass, and commercial brass all has much thinner case rims than what British military ammo has. This increases headspace, and allows the brass to expand more to fit the chamber. If you full length resize each time with your die adjusted to the manufacturer's instructions, the case shoulder is pushed back to somewhere near it's original location. You shoot that round and the case shoulder moves forward again, trying to fit the chamber. After a very few cycles, the brass separates just above the case head, at the weakest point. If you retain the fire-formed dimensions of the case and merely neck size, the brass doesn't have to expand to fit the chamber again, and again, and again. Granted, after you've fired that piece of brass several times, you will need to FL size it. The trick here is to adjust your sizing die so that it moves the case shoulder back just enough to allow the case to freely chamber. I adjust the FL die down a bit at a time, trying the case in the chamber each time until the bolt just closes without resistance. Then I lock the die's lock ring down. If RCBS made a Precision Mic or Redding made an Instant Indicator to measure .303 brass, I would use one of these tools to measure how much I am sizing my brass. Since they don't, all I can do is the 'size a little bit and try it' routine. Probably more than you wanted to know, but this topic gets a lot of discussion on some of the C&R forums. |
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Wow! I cant believe the varying opinions here! I collect British firearms, I have a safe full of enfields. A few of them never go to the range because of collectors value, but many of them do. When I load 303 british I never do anything special. All cases get the full length sizing, and everything. I"ve never had a problem. Brass expands with heat, that's why you full length size, and trim. You need a good set of head space gauges. I've noticed that on some of my older enfields that the cases expand alot more when the bolt closes on a field, and accuarcy sucks! I've never had issues with case expansion or accuracy on the ones that close on a no-go though. So, why only do part of the job? I've been loading for these old ass guns for years and never heard anyone say anything about partial sizing. Dude, just run em' through, load em' and shoot em'!
Oh, and slug your bore! some have been eaten out enough that you may have to use a .312 dia. bullet instead of .311, you will get better accuaracy. |
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Listen to SteelOnSteel and Bog_Irish
Other wise expect to get very short brass life. The No.1 chambers were only a little large by military standards of the day. To assure function with rusty, mud caked ammo, the No. 4 intensionally had HUGE chambers. The body diameter was particularly oversize. You can do this with rimmed cartridges since the case body can hang in mid air as long as the rim fits right. As has been said - segregate brass by rifle and neck size only. A No 1 may get OK brass life with FL or partial sizing. The No 4 chambers are very large in body diameter so if you attempt to partial size, you'll be squeezing down the body and extruding the shoulder forward, so you end up practically FL sizing anyway. In this situation the cases will fatigue quickly. In the past you could send 3 or 4 fired cases from your rifle to RCBS and they would cut a FL die for your particular .303. I don't know if they still do this or how much they charge. Brazos_Jack |
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Quoted:
Wow! I cant believe the varying opinions here! I collect British firearms, I have a safe full of enfields. A few of them never go to the range because of collectors value, but many of them do. When I load 303 british I never do anything special. All cases get the full length sizing, and everything. I"ve never had a problem. Brass expands with heat, that's why you full length size, and trim. You need a good set of head space gauges. I've noticed that on some of my older enfields that the cases expand alot more when the bolt closes on a field, and accuarcy sucks! I've never had issues with case expansion or accuracy on the ones that close on a no-go though. So, why only do part of the job? I've been loading for these old ass guns for years and never heard anyone say anything about partial sizing. Dude, just run em' through, load em' and shoot em'! Oh, and slug your bore! some have been eaten out enough that you may have to use a .312 dia. bullet instead of .311, you will get better accuaracy. This is not just ".....opinions here....". This problem is also written up in reloader manuals edited by professional ballisticians about the Lee Enfield. If you buy new brass, full size it, take your safe queens out for a run once a year, you may never have experienced the problem. If you want to get 5-10 cycles out of the brass, then you should heed the warnings about full sizing in extra large chambers. Slugging the bore is an excellent idea for any war surplus gear. |
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