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Post by TGinPA on Feb 3, 2014 20:51:21 GMT -5
Maybe >10 lbs seating press?? One hand, 3 fingers??? This was a proof of concept test. It does need to be repeated. But I am down to my last 5 275be so have to use them wisely. TG
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Post by rambler on Feb 3, 2014 20:56:25 GMT -5
this is extremely cool!!! I greatly appreciate the privilege of reading and learning this stuff from ya'll
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Post by Deleted on Feb 3, 2014 22:49:58 GMT -5
Was the primer cup used for the LRM used under a load before or did you just pop one off and punch it out to reprime it? Just wondering if a second exposure to pressure caused the bulge. Thanks for taking the time to do this.
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Post by edge on Feb 4, 2014 6:44:56 GMT -5
SNIP Standard Savage plug modified for Fishhawk bushing. SNIP What is the approximate distance of the BP from nipple to the powder side of the Fishhawk bushing? This is a 0.031 bushing? edge.
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Post by hankinsrfls on Feb 4, 2014 14:48:56 GMT -5
OK, so the load shot with the 209 primer has a higher peak pressure and velocity? And we're talking loose fit bullet like the Hankins gun? Interesting! I can't wait to see the results for the slower powders. Thank you! Look at the bulged primer carrier used to hold the LRMP compared to the one that was stock 209. It's obvious that there was more pressure with the LRMP. You can also see the black smoke around the primer. This means it leaked pressure out the back just like blowing a primer pocket in a center fire. Thus causing a false reading on the pressure trace. ..
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Post by edge on Feb 4, 2014 15:06:24 GMT -5
Look at the bulged primer carrier used to hold the LRMP compared to the one that was stock 209. It's obvious that there was more pressure with the LRMP. You can also see the black smoke around the primer. This means it leaked pressure out the back just like blowing a primer pocket in a center fire. Thus causing a false reading on the pressure trace. .. Not sure I buy that theory, but maybe 1) The shape of the curve seems too uniform, I think that some flattening would be seen if there were pressure leakage. 2) The test has too few samples to know that the reverse might happen the next time, perhaps just a weak 209 cup. 3) If it leaked pressure then indeed the pressure was lower and so why would it bulge with lower pressure? edge.
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Post by Deleted on Feb 4, 2014 16:03:27 GMT -5
The bulged primer carrier looks a little like what you see when you shoot a high pressure round in a semi automatic handgun with an unsupported chamber... In the same sense the primer in a Savage breech plug also sits in an unsupported chamber... The bulge in the unsupported area seems to indicate higher than normal pressures.. What baffles me is practically identical pressure traces and velocities..Also the velocity of the LRMP that was tested is very close to What Hankins gets in his plug... Maybe the answer lies in the way the primer is enclosed in the primer carrier not allowing any pressure to escape causing better ignition... If the test could be reversed using a 209 primer in an enclosed system like Hankins builds it might help answer the question... I'm liking the fully supported ignition system that Jeff has to offer. ZeN
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Post by hankinsrfls on Feb 4, 2014 16:03:32 GMT -5
Edge.. IMO the bulge came first then released some gas pressure. You are correct about needing to do several traces to see if it keeps reading the same,, but I don't think anyone can deny that the primer leaked gas. If it didn't I would not be smoked...
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Post by TGinPA on Feb 4, 2014 16:52:21 GMT -5
FWIW, today, I did a repeat LRMP pressure trace with Hankin's load (I4198 78 gr 275be) at the same temperature (60-62deg)of the 2/3/14 pressure traces posted earlier in the thread. This time, the carrier casing used to contain the LRMP was from a Fed209A primer discharged without any powder load in front of it. To look for blowback, I placed a white paper towel covering over the bolt and breech area, holding the towel in place with a sandbag placed on top. The pressure tracing obtained was close to identical to the one recorded on 2/3 ((49.9kpsi V=2883fps). The towel that had been used to cover the breech area was blackened at the front of the bolt and and at the areas where it covered the safety ports on either side of the breech, indicating significant blowback. TG
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Post by Deleted on Feb 4, 2014 17:12:23 GMT -5
I would guess the primer cup just isn't going to be substantial enough to eliminate blowback when fit with the inappropriate primer internals. At least we know this test is repeatable in more than one trace. Did this primer bulge similar to the first trace?
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Post by TGinPA on Feb 4, 2014 17:23:09 GMT -5
Yes. It did. TG
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Post by Dave W on Feb 4, 2014 17:35:03 GMT -5
Edge, the handi rifle conversion you did with the brass or copper two piece plug. Was it 209 powered or LRP and/or did you try it with both types of primers. If so, any differences. Was thinking it was a supported 209 but can't remember?
Tg, do you have some way of monitoring the heat in the barrel? If so, maybe fire a random number of primers on an empty barrel, check barrel temp, let barrel cool to ambient temp and repeat the test with the other primer option. If the LRP s are that much hotter then I would think there would be a higher residual heat build up and blow back would not be an issue?
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Post by edge on Feb 4, 2014 17:53:01 GMT -5
I can use both 209 and LR primers inserted into a 45 acp case. With straight powders I get some misfires with the LR but NEVER with the 209, but it is not 100% sealed since the BP was designed for a 209 and the LR was only an afterthought. If I were to start from scratch I would make a positive lockup and machined the inside base of the ACP to an exact dimension. IMO the ACP case varies too much. I do get some blowby but it does not bother me, take a wipe after shooting and I'm done. Also if I were to start from scratch I would not use an 11/16 thread diameter either but we got our start with the Savage plug. My H&R plug still works and actually has less blowby but I did machine the inside base of the modules. Would I feel OK with a 60kpsi load NOPE, but it should be fine for the 45-70 loads that it was designed for edge. PS I made a BP for someone else and he is "very" picky about blowby
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Post by fishhawk on Feb 4, 2014 21:33:02 GMT -5
I noticed something based on my work with sticking primers. The pictures TG posted with both primer setups showed the flattening of the 209 around the firing pin strike (TG noted this) which is fairly normal for higher pressure loads from either a Savage 10ML or Hunter 700ML nose. IMO this is where it was forced back against the boltface which usually results in the cups flange being forced forward until the flange is stopped by the top of the slot for the flange. Where as the LMRP face did not protrude likely leaving the flange against the bolt face throughout the firing process. If the 209 primer carrier moved forward it was supported more than the carrier that likely stayed against the boltface. A Savage 10ML2 bolt flange slot is .048" tall, and a Fed 209A flange is .023" thick, so the primer can move forward .025" when fired. A Hunter 700ML slot is .038" tall, so the primer can move .015". Is this enough to make the primer cup walls supported more reducing bulging? beings it is forced forward more, is it sealing better? I feel we might be apples to oranges? Now to make a better comparison, if we had a .015" or.025" shorter nipple on a plug for the 209, or a way to keep the 209 against the face. One of Hillbill's cures for sticking 209's on a Hunter nosed 700ML was to shorten the nipple. This may have allowed more leakage, or expansion of the diameter of the primer cup near the flange. I hope I'm making sense, I swear I haven't been drinking....
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Post by Deleted on Feb 4, 2014 21:58:27 GMT -5
Correct me if I'm wrong but isn't a win 209 longer in length? Therefore it would create a better seal than the fed 209? So if the test was done with a win primer would it yield different results?
RR
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Post by longrange on Feb 5, 2014 6:35:01 GMT -5
I'm not sure if this is relative to the test, but I done a primer test with my 300 wsm. With everything else the same, velocitys with CCI lrmp were always 50 fps slower than with winchester lrmp.
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Post by longrange on Feb 5, 2014 8:24:10 GMT -5
My point is,Changing components can change velocity and pressure. If the test were repeated using Winchester or federal lrmp it might tell a whole different story, or maybe not. My results might be specific to my rifle and load.
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Post by edge on Feb 5, 2014 9:13:04 GMT -5
FWIW, today, I did a repeat LRMP pressure trace with Hankin's load (I4198 78 gr 275be) at the same temperature (60-62deg)of the 2/3/14 pressure traces posted earlier in the thread. This time, the carrier casing used to contain the LRMP was from a Fed209A primer discharged without any powder load in front of it. To look for blowback, I placed a white paper towel covering over the bolt and breech area, holding the towel in place with a sandbag placed on top. The pressure tracing obtained was close to identical to the one recorded on 2/3 ((49.9kpsi V=2883fps). The towel that had been used to cover the breech area was blackened at the front of the bolt and and at the areas where it covered the safety ports on either side of the breech, indicating significant blowback.TG Have you performed the same test with the 209 primer to see how much blowby you get...if any? edge.
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Post by rambler on Feb 5, 2014 10:37:54 GMT -5
i have been following this thread closely. As most of you know i'm new to smokeless ML'ing. Is the 209 still going to be a good choice for ignition systems in general??
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Post by rangeball on Feb 5, 2014 10:43:18 GMT -5
I believe so. I wouldn't hesitate to order a plug or SML with 209 as the primary ignition. If testing proves out the LRMP is better I have no doubt the cutting edge minds here will develop an alternative for those wishing to easily convert from 209.
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Post by ET on Feb 5, 2014 11:06:10 GMT -5
I’ve been following this primer comparison test with a bit of interest. I agree with Edge that this limited test doesn’t necessary reveal all.
If the testing is to reveal the ignition strength then a movement test with primers only might possibly be helpful. With the production of specific heat from solid to gas there also has to be an associated specific pressure generated with it. By measuring the response from this level of pressure may reveal more.
Ed
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Post by rambler on Feb 5, 2014 12:32:34 GMT -5
well, all i now is alot of people are having some great results with the 209. I'm going with the old stand by technology for now. I've got no choice my gun is in the works already
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Post by TGinPA on Feb 5, 2014 16:52:52 GMT -5
TG [/quote]Have you performed the same test with the 209 primer to see how much blowby you get...if any?
edge. [/quote]
Not yet.... TG
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Post by rangeball on Feb 7, 2014 14:09:24 GMT -5
Something I've been wondering about. I've seen claims (not just here) that LRMPs are hotter but with less pressure than the 209. Cecil claims it, and says the added pressure from the 209 causes the load to move forward before full ignition, causing fliers.
He stated he tested this-
I have no idea if he was able to control the seal for no blow back or pressure loss, but I would be interested if at all possible if TG could duplicate this test if he is up to it. I would hope with no powder the pressure leak he saw with the LRMP would not appear. If the LRMP does in fact produce hotter gasses than a 209 but with less pressure, I still think that may be the missing factor, and I'd love to see it proved one way or another.
To this point even if the LRMP produces less pressure when it ignites, I would suspect if the theory holds true that it is also hotter it would provide a higher full load trace pressure, as there would be more complete ignition before the load starts moving forward. Just because it may trace higher doesn't necessarily mean that the primer itself has a higher ignition pressure than a 209.
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