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#1
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Plunk test
My dummy round failed, what should I look at, OAL or flaring?
Using 45acp LRN, OAL is 1.250, case(neck) flare is .471 She sticks in barrel and is about .062 outside from flush with barrel. I should just go in more with bullet, do you think I have an issue with flare? Let me know if you need more info
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I like to keep it simple, cause I'm getting older |
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#2
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I would measure the chamber to the back of the hood with inside caliper. them I would put the barrel in the slide with a the loaded round and push the barrel all the way to te rear and the bullet forward and check the clearance. If you stick the loaded round under the extractor first and slip the barrel in it is easier to do.PS:Idid not see the .062 number you probably have a unfinished chamber that needs finish reamed.Was it .0062?
Last edited by supervel; 05-01-2012 at 01:48 PM. Reason: finish reamed |
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#3
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Many cast 230 gr RN bullets have a very pronounced shoulder and a short nose. It is quite possible that the bullet is hitting the rifking and stopping there. If the bullet you are using hase the shoulder you may need to seat deeper. When I load RN with the shoulder I do it the same way that I do SWCs. Measure the length to the shoulder, it should be about .935". Any longer and that should will many times hit the rifling.
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Don't believe anything you hear and only half of what you see. USPSA A-27738 Allan |
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#4
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Quote:
If it is really easy to push the cartridge flush, I'd say drop the crimp back to .469 and see how the round "plunks" for you. If you're feeling some real resistance, I'd try seating the bullet .005" or so deeper and see how it plunks. |
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#5
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Quote:
Last edited by supervel; 05-01-2012 at 05:59 PM. Reason: change troat to chamber |
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#6
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The Plunk test can be misleading. A short hood will make it Scued also.
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#7
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I agree with Alland. My crimps are at .471-.472". With lead RN I have to set my OAL to 1.240. My plates RN bullets seat at 1.260". I tried seating my lead bullets at 1.250 and had the same problem.
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Pistols:XD40sc, XDm40, SA Loaded The reason I carry daily I'd because I'm too young to die and to old to have my but kicked! |
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#8
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The easiest way to tell if the problem is the crimp is to reduce the crimp to 0.469" or 0.470", if the round still does not pass the plunk test you will need to shorten your OAL. 0.471" should be in the ballpark so I'm betting the problem is either your OAL or shaved lead.
Are you seating and crimping in the same step? I ran off a lot of 400 rounds (225gr LRN) and had the same problem as you are experiencing. The die must be ajusted almost perfectly and probelms with cast bullets can still happen. If the die is not ajusted correctly the die will start to crimp the case while the bullet is still being pushed into it. A slight roll of lead forms at the case mouth and prevents the round from chambering correctly. The answer to this problem is to seat without crimping in the first step then crimping in a seperate step.
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Molon labe! It's not what you take with you when you leave this world behind, it's what you leave behind you when you go! |
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#9
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No I can not force it flush to the barrel, if I did I may not get it out unless I use some pry tool, my fingers would not get it out.
I'm using lee carbine dies, and I'm seating in one die and using a LCD die for crimping I'll check the Shoulder
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I like to keep it simple, cause I'm getting older |
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#10
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Sounds like seating depth then.
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#11
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Ok well I'm out here now, I'll be adjusting and let ya guys know when I pass
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I like to keep it simple, cause I'm getting older |
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#12
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TW45 - take a colored marker and paint the nose of your bullet. Insert it into the chamber and tap it with your hand. Then remove it from the chamber by tapping it out from the muzzle end using a wood dowel or some other non metallic instrument, even if it's a screwdriver that''s been taped over to cover the metal. If the colored markings are scratched, your seating length is too long for those bullets. Run them through your seating die in small increments until they seat flush with your hood. Horoscope Fish asked about this, but we didn't hear a response. Sorry, can't type fast enough!
In my opinion, your crimp is fine, it's the COL for your particular chamber that needs to be addressed.
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RIA M1911A1 FS CZ 75B 9mm Ruger SR9 S&W M&P 15-22 |
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#13
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Yup sounds like you need to seat the bullet a little deeper, you may need to lower the powder charge if you were on the high end.
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NRA Life Member Doubt: The only thing I'm sure of. Fear: The only thing I'm afraid of. |
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#14
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I have it flush to .010 under at a OAL of 1.216
But it still seems it sticks in the barrel, I can hold the barrel up side down and the cartridge will not fall out freely, I give it some firm jiggle and the the cartridge will fall out. Normal?
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I like to keep it simple, cause I'm getting older |
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#15
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Quote:
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I like to keep it simple, cause I'm getting older |
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#16
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Quote:
That OAL would be way too short for a 230 grain, however, which is why I'm asking... |
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#17
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This is what's working, AOL 1.206 with a crimp at .469
She plunks in freely and falls out freely, what you think of the numbers, a bit small on AOL? Sorry it's a 230gr LRN
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I like to keep it simple, cause I'm getting older Last edited by TW45; 05-01-2012 at 03:40 PM. |
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#18
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That's a pretty short OAL for a 230 grain LRN in my experience, but it could be the bullet you're using... And it *is* passing plunk testing, so chances are it's fine.
That being said, what bullet, exactly, ARE you using? |
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#19
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there are many factors to consider for a good plunk test. as always, the acid plunk test must be accomplished in the chamber/barrel of your gun, and nowhere else. factors that can make for a bad plunk test are - the crimp diameter, oal, bullet shape, case length (for rounds that head space on the case mouth).
if a load recipe calls for a particular bullet type/shape, which dictates a specific oal, and you build a dummy round that fails the plunk test in your gun's chamber (too proud of the hood, sticks, etc.) and you reseat the bullet a tad deeper and it shortens the oal, you are not building to the load recipe and an unsafe round may be the result ... is your bullet the precise same as dictated by the load data and you are not substituting a different brand, type, shape? is the case length to spex or under spec'd? is the crimp correct and matches or is under the load data recipe? is your barrel's chamber clean? when i load 230gr missouri lrn for my rem 1911r1, i use an oal of 1.245" for a perfect plunk test. most 1911's feed well with lrn's, but the shape of lswc's will be easier to plunk test (and hopefully they will feed well in yer 1911) ... the lswc plunk test
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NRA Life Member ~ MOLON LABE - Leonidas, 480 BC |
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#20
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Ps: If you plunk it to many times I have seen 230FMJ actually grow in lenght slightly durning the test with a factory round and had to seat it back to lenght, not that this is your situation, but it is good to know.
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#21
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and why/how does that lengthening occur?
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NRA Life Member ~ MOLON LABE - Leonidas, 480 BC |
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#22
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Quote:
I moved in very slow and once I got under a OAL 1.21 it finally started to flush with my barrell, I then played with this some more and crimp to come up with above number in your quote of me saying 1.206 with a crimp at .269 This is the number that flushes with barrel and plunks in and out
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I like to keep it simple, cause I'm getting older |
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#23
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i had similar problems, i lowered the fcd down almost touching the shellplate
it removed the remaining bulge and they seat just fine.... this is what i found, and you may have a different problem, if you have not try it, just might work...???? |
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#24
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Quote:
Newbie here whats the vocabulary on fcd and shellplate?
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I like to keep it simple, cause I'm getting older |
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#25
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I test fired 4 rounds at 5grns
cartridge measure .473/.475 with a shorter OAL than normal I posted pics of the primers also, see what anyone thinks? to much pressure for a 1.206 OAL 45acp? ![]() ![]()
__________________
I like to keep it simple, cause I'm getting older |
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