Armory Sponsor
Posted: 4/12/2009 8:36:56 AM EDT
|
Could someone help me out a little here? I just started reloading 9mm and am starting with some plated 9mm 124grain bullets with Hodgdon Tightgroup powder. Most of the data I have found states a starting load at 4.1 up to 4.4. Some data say start at 4.0 and one source starts at 3.6 (got that through Hodgdon website) and the bullet had an abreiviation of LCN while the rest of the data was at 4.0grains starting load.
I loaded five rounds at 3.6 and five at 3.7 for starters and fired them from a glock 17. If you are familiar with that handgun there is a little rectangle that the firing pin comes though and this was leaving a slight imprint on the primer of the 3.6 loads. I took it as a sign of overpreasure so I stopped and started searching for more data. A friends books (3 of them) all produced the same loading data. I read a little more and found that "cratering" could be a sign of having too low of pressure sooooo..... I load five more rounds at 4.1 grains... Fired the 3.7 and the 4.1 and got the same result with all ten rounds, no other adverse signs noted. I do not know what to make of the little imprint on the primer, it is very slight but concerns me since I can not explain it. Other info Case length .753 Overall Length varied between 1.167 and 1.170 |
|
Cratering actually looks like a crater with a rim. Sometimes, visuals on fired primers do not tell the story. I don't think you have a problem. You did the right thing checking more sources. If the bolt/slide has imperfections, or machine marks, these will be transferred to the primer. Have fun. |
|
Re-read and look closely........
Overpressure signs (photos), look about half way down the page….……. http://www.radomski.us/njhp/cart_tech.htm And………. http://stevespages.com/diagnosingproblems.html Note, rifle ammo will usually operate at a much higher pressure. And, the design of a rifle is usually much different from that of a pistol. Anyway.......I've found that reading rifle primers to be easier. Then, what about: design and condition of the firearm itself? And consider that, just reading primers doesn't say very much due to differences in primer pocket "tightness" and the primers themselves. But, some stuff can still be considered a "universal warning." So............without pictures, it's a SWAG as to what you're seeing/dealing with. One other universal truth.............."Reloading Data Varies." Aloha, Mark PS...........I don't own a GLOCK and I don't use Tightgroup. So, I can't say about what's "normal" for a GLOCK with Tightgroup. ______________________________________ And YES, I have seen fired brass out of a GLOCK. Why does GLOCK (or HK) do things the way they do? Well, they have made millions and I can't argue with success. Maybe, it's a European thing (anti re-loading)? |
|
I haven't been reloading 9mm too long and I also use Titegroup powder. I have a G35 with a 9mm conversion and a M16/9. I was shooting some 147gr over 3.5gr TG the other day when I picked up a piece of brass that had come from my G35 and was also concerned about the rectangle that was left on the primer. I loaded some WWB 9mm and shot and the primer also had the rectangle. I put some WWB and some reloads in a AR mag and shot a couple. All the brass looked good and the primers were also good.
I wouldn't worry about it. |
| The LCN=Lead Conical Nose, and that is good cause with plated bullets you should stick with lead bullet data rather then jacketed. Titegroup is good powder.....but it is a low charge wt/volume powder. Another problem that can be an issue is if you do not seat the primers below flush, make sure you can feel a dimple in the fully seated primer when you run your finger over the case head. TG is not exactly the best powder for a noob reloader as it is very fast burning, and it needs a good crimp. But, with plated bullets you need to be cautious with crimp cause too much can strip the plating away from the bullet. Guess that automatic reloading machine thing did not come your way? |
|
I load 124gr 9mm with TG. I've found that guns often don't function well below 3.8gr. 4.0 is good for about 1020fps - shoots soft, reliable, and accurate in every gun I've tried. I've shot over 10k rounds of this load. 4.2 works fine too and has just a touch more recoil.
TG is known to spike pressure at a certain point. However I've been messing with some hotter 147gr loads lately, and I'm now 1/2 gr over the max load in the Hodgdon manual. I am only just starting to see some pressure signs. If you stay within the loads in the manual, you'll be fine. |
|
Quoted:
Could someone help me out a little here? I just started reloading 9mm and am starting with some plated 9mm 124grain bullets with Hodgdon Tightgroup powder. Most of the data I have found states a starting load at 4.1 up to 4.4. Some data say start at 4.0 and one source starts at 3.6 (got that through Hodgdon website) and the bullet had an abreiviation of LCN while the rest of the data was at 4.0grains starting load. I loaded five rounds at 3.6 and five at 3.7 for starters and fired them from a glock 17. If you are familiar with that handgun there is a little rectangle that the firing pin comes though and this was leaving a slight imprint on the primer of the 3.6 loads. I took it as a sign of overpreasure so I stopped and started searching for more data. A friends books (3 of them) all produced the same loading data. I read a little more and found that "cratering" could be a sign of having too low of pressure sooooo..... I load five more rounds at 4.1 grains... Fired the 3.7 and the 4.1 and got the same result with all ten rounds, no other adverse signs noted. I do not know what to make of the little imprint on the primer, it is very slight but concerns me since I can not explain it. Other info Case length .753 Overall Length varied between 1.167 and 1.170 All Glocks do that, even with factory ammo. |
Armory Sponsor