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I'm hoping to get a clearer understanding of what is and what is not a risk when reloading my 444 Marlin. Or any rifle for that matter. Just learning the new art of reloading and enjoying it very much. I have just finished testing my 444s rifle with 52 to 56 grains of Hodgson H335 powder pushing 330gr. beartooth bullets. The only difference in the brass after firing 54, 55, 56 grains of powder and then comparing the brass to a factory fired load was a miniscule difference in the primer impact point. What I mean by this is the dimple left by the firing pin had a slight (very slight) wave or shoulder, if you will. I'm having problems explaining myself. - Factory primer has a hole where the pin strikes the cap. - Reloads all had a shoulder on it when you run your finger nail on top of the impression. The brass was fine. The rifle was not sticky to open. there is considerably more recoil but that is to be expected. I believe that this may be the first signs of hi pressure but is it enough to back off? I don't see that it is detrimental to the rifle in anyway and the load has been tested (refer to beartooth bullets tech notes) BUT there was a difference. So what do you think Yeh or Neh? Regards Bellhender | ||
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So you're getting a hole in the primer? The dimple you mention, is it cratering? Eithr way if you're getting a hole that is not good. What velocities are you getting? I use 56 gr of H335 with the 300 XTP (have gone to 57gr with no problems). For the 355 gr Beartooth I use 45 gr RL-7...2150 fps and ouch a kick from hell! | |||
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If you are not loading to hot try different primers I have been told that some are hotter than other and could increase pressure. But from my past experience with rifle cartridges I would say back off the charge it sounds like a pressure issue. Swede44mag | |||
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Thanks for the response Pop. There is no hole just a very small dimple(hardly noticeable) on the edge of the indentation caused by the firing pin strike. It may be nothing as I have not met a person who used this load that thought it was over pressuring their rifle. My problem is I'm new at this and don't know what is and what is not a pressure sign. | |||
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Quote: Hey Bellhender, I don't know if it is enough to back off a bit or not, but I do know how to find out. Your info about the Load having been Tested by Beartooth Bullets probably means it is fine and SAFE in your rifle, but below is how you can find out for sure. ... These typically Lower Pressure cartridges lend themselves real well to measuring the good old Pressure Ring Expansion(PRE). You can locate the Pressure Ring as the widest diameter forward of the Rim on a fired(and not Resized) 444MAR case. You need to have a set of 0.0001" capable Micrometers in order to read the PRE with enough accuracy to make it useful. (A 0.001" Caliper just isn't accurate enough.) 1. Shoot a box of new Factory Ammo through your rifle. 2. Measure the PRE by rotating the Pressure Ring between the anvils of your 0.0001" capable Micrometers. The largest measurement you can read that will cause the Pressure Ring to "hang" the case between the anvils is the number you are looking for. Do not "force" the case to turn, or you will skew the data. EXAMPLE with FAKE values: Let's say you measured the cases and they ran from 0.4690"-0.4696" and after you Averaged them the PRE was 0.4694". Then write 0.4694" Avg PRE on the box those cases came in. 3. Full Length Resize those cases, reload them with your Test Load, shoot them and compare the PRE of your Reloads with the Factory Standard. 4. When your PRE is the same as that of the Factory Ammo - STOP. That way you will know for sure your Load is completely SAFE. 5. Depending on the strength of your Reloads, these cases should give "usable data" for maybe 6-9 reloads. Then use them as Plinker Cases. ... The visual appearance of the Primers is one thing to consider, but it is difficult for a person just beginning to Reload to understand the subtle differences. In this particular cartridge, many of the old Pressure Indicators don't work because you are already well beyond a SAFE MAX by the time they show up. Good luck to you. ... What size groups were you able to get with those Loads? | |||
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Hot Core, Perhaps you should explain the Pressure Ring location more precisely. If he is measuring the case head (solid disc of brass with just the flash hole piercing it) and getting ANY expansion before and after, he is OVER PRESSURE by a sizable degree. The pressure ring is forward of the case head and is a way of estimating pressure based off of barrel radial deflection during firing. As such you MUST measure the case in EXACTLY the same place and ACCURATELY to 0.0001" of for the measurement to be anywhere NEAR ACCURATE. This is the same methodology employed when strain gages are fitted to a barrel, in case anyone was wondering. ASS_CLOWN | |||
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When you full length resize the case, you will notice that it may be a lot harder to lower the handle on. That can indicate that you are having an excess amount of pressure. Or if after a load or two the primers are going in way too easy. As someone who also loads a 444, You are a lot better off using a fast powder. Secondly, the bullets in a 444 are not very aerodynamic at all. I shoot a 300 grain XTP as my main bullet in mine. If I decide to live with 1750 fps MV instead of 2100 fps MV, I reduce recoil substantially, and loose about 10 to 15 yds of point blank range. It surprised me, but what I saw in the trajectory charts, I verified at the range. I take loads from the 44 mag in a rifle and work up a little bit. I use Blue Dot shotgun powder. It is the first round I tried it in after I learned about its use in the 223. I should probably get off on my fanny and do a range report on Blue Dot and the 444 Marlin. Cheers and Good shooting seafire | |||
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Quote: Hey Bellhender, Good scoop from Seafire about the "reduced velocity" not being a performance killer with this cartridge. It still packs a lot of whallop. Point being, if you load a bit low, it dosen't cost you anything and the plus is longer case and rifle life. Quote: Hey Seafire, Excellent idea. Look forward to the thread. | |||
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Quote: Hey AC, Maybe you missed this sentence in my post, "You can locate the Pressure Ring as the widest diameter forward of the Rim on a fired(and not Resized) 444MAR case." I do agree with you when you said, Quote: I also agree somewhat with, Quote: The only problem with saying "estimating pressure" is it gets a whole lot of the Strain Gauge folks thinking you can determine a specific Pressure in PSI using PRE, and I've not found that to be the best way to think about it. If the person using PRE thinks of it as simply a "comparison" to a previously established Factory Expansion Standard, they need not be concerned about what the actual PSI Pressure is at all. When talking about Case Head Expansion(CHE), I agree with, Quote: But when measuring PRE I've found that rotating the case to locate the "typical" high spot on the Pressure Ring works best "for me". As you mentioned there is the Barrel's Radial Deflection, normally a slightly thicker and thinner portion of a case wall, and some chambers just aren't always perfectly circular, which all affect the measurable Pressure Ring. If you measure in "one spot" for PRE, your data can get slightly skewed due to all the above. However, rotating the case to locate the "high spot" tends to nullify those uncontrollable variations - for me. Good luck to you. | |||
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Well thank you for the input Hot core, Seafire, and Ass Clown (different handle there buddy but hey it's a brave new world out there) There is no scope on my rifle so the downloading and losing a bit of range seems like an intelligent option. I don't believe I could be accurate enough to measure the tolerences down to 1/1000. My machinists ticket never did get finished. It appears I'm going to have to get better tools and learn to use them if I want to push any envelopes and for now I just want a powerful load for my little bush gun. All the brass are new (0 to 2 firings) So I think I'll leave it at 56 grains and watch for weaknesses in the brass. For practice purposes I'll download and keep my aim inside 200 yards Thank you all for your input it is much appreciated. | |||
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Hot Core, I believe we are pretty much in 100% agreement. You have done a better job explaining yourself than I have done. You are correct in that I missed you comments about finding the "pressure ring". So please accept my apology for spouting off, again! I would say that it has been my experience that the most repeatable position on the case is slightly forward of the "pressure ring" definition you have provided. I sectioned several cases and found that if I measured just forward of the termination of the blend radius between the case head and case body, I got more consistent case measurements. My hypothesis on this is that there is less "spring back" associated in this region since the case is far thinner hear (typically 0.015" thick). PRE, if done correctly, in my opinion provides a good A to B comparison between loads. It does in many ways mirror strain gage methodology, with the major difference being that in strain gaging one is measuring the barrel itself, not the brass. ASS_CLOWN | |||
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I'm currently using 56gr H335 with both Speer 300gr and Beartooth 330gr bullets without "sticky" cases, or noticeable case expansion...but yes, the recoil is enough to wake you up. | |||
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My Quickload/Quicktarget program thinks that it take ~108 yards for a 300 gr .430" XTP to slow from 2100 to 1750 fps. I don't KNOW what the truth is, nor do I have any ambition to shoot a 300 gr slug at 2100 fps from a light rifle. | |||
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Quote: Hey AC, Were are in agreement, in agreement and completely in agreement.  What I described as the Pressure Ring is exactly that point on the Case Body where it "thins" forward of the thicker Web that the Flash Hole is drilled through. It is easy to locate on a "Fired Case", because you can see and feel it. Once you either Full Length Resize or Partial-Full Length Resize(which I prefer), it is even easier to see because the Die "burnishes" the Case and creates a shinny thin ring at this spot. This is also the same place where Case Head Separations occur when Cases are not Resized properly. To me, the Case Head is the portion of the Case just forward of the Extractor Groove. On a Belted Case, it would be directly across the Belt(if that helps anyone else). I know Clark has good luck measuring the Extractor Groove Expansion on "higher Pressure" cartridges. Here you are measuring the expansion of the case around the Primer. And as long as a person is consistent, the data is worth gathering. I've also known some folks who have "tried" to measure Rim Expansion. Various problems here. By the time the Rim expands, you've gone too far. And the Extractor, during the act of Extracting the Case, can distort the Rim giving erronious data. ... I don't have a lot of use for the Strain Gauge Systems(SGS) outside a Lab. Lots of inherent problems with them from getting the initial measurements from the firearms chamber area "accurate enough" to be meaningful, to not being able to Calibrate the SGS to a known "Standard". Lots of folks have them and use them to develop some good SAFE Loads. Good for them. Then there are others who use them in a manner in which the data they provide to Rookie Reloaders is not only misleading but dangerous. The typical Rookie doesn't understand enough about Cumulative Metal Fatigue to really know how this can "occasionally" be a problem. This is in no way an assault on your having a SGS. ... For what it is worth, I can see the humor in your name. At the same time, I can also see you have a good bit of Reloading knowledge and firearm moxie that some folks are likely to skip on by because of that particular choice of name. Darn shame, cause it looks like you can be a valuable assett to the Beginners. ... Hey Bellhender, First off, your welcome! A lot of folks will try to scare you off from learning how to use a $20 set of 0.0001" capable Micrometers when they shouldn't. It just isn't that big of a deal to learn how to read them. All you are doing is tightening and loosening a precision "bolt through a fixed nut" and then reading some numbers. Any Shop Instructor, Tool/Die Maker or Quality Assurance person could show you in 5 minutes. I've got a good many 444MAR "Test Loads" setting in my Range Box ready to go try myself. More storms passing through right now here. Anyway, keep us informed about how well your rifle does with them. Best of luck to you. | |||
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