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Posted: 5/17/2008 8:13:48 PM EDT
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I went to the range again and my handloads are shooting low about 1.5-2.0" the sights are fixed on my XDSC 9mm My handloads are 124g Remmington with 4.3g Titegroup and a OAL of 1.155-1.158" with a CCI 500 primer |
| What do you mean by light load? is the bullet to light or is the charge to light, I am loading them with 4.3g the max is 4.4, yes the groups are not bad they do fire to the left but I can adjust windage but the only way to correct for low is to shoot higher off POA , the barrel is only 3" and has a very short sight radius but it's shoots well with S&B Comm loads, will changing the OAL have any difference? |
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Light bullets shoot low, heavy bullets high. I took three different .44 mags with five different bullet weights and different velocity loadings to the range and shot all the loads on the same target per each gun. Basically bullet weight was the biggest factor. The spread was about 10" at 35 yards from the 180 gr. bullets to the 300 gr bullets. Lead and Jacketed bullets of the same weight with wide velocity differences still hit at close to the same point of impact. Try it yourself, YMMV Jim |
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I have heard that varying the OAL will also affect accuracy, the range for the 124 FMJ RN is 1.135-1.169 I am currently at 1.155 ( I just split the difference )also I am curious about the 4.0-4.4 range on the charge I started at the minimum and have worked up 1/10 at a time and have not noticed a major difference in POI, I know the velocity goes up but what do you base powder charge on it looks like the velocity range is 1000-1250 depending on powder and charge Like I have told several I am very, very new to reloading and don't understand all the variables |
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The changes in velocity you are dealing with from those small changes in charge weight will have very little effect on point of impact. On a pistol, the point of impact is a function of dwell time. Heavier bullets will have a longer dwell time in the barrel, during which the pistol will recoil more and raise the POI. Lighter bullets the converse. You don't state your range for firing but with a fixed sight pistol, a 2 inch difference in point of impact is pretty insignificant for most purposes. |
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I am shooting at a distance of 7yrds out of a SA XDSC which has a 3" barrel and fixed sights, the windage is adjustable but not the elevation. I will most likely go with a 4.2g charge but what determines the OAL ? the COAL tested for a Speer 124g FMJ RN is 1.135" but I am using a Winchester bullet so do I set the OAL to 1.135 in accordance with my Speer manual or do I leave it at 1.155 and aim high |
Welcome to reloading. I can not answer that question. Only your pistol can. Make some rounds with different OALs and see how that goes. My general OAL is 1.070 to 1.1. You really want to drive yourself batshit buy 4 different types of primers and 10 different powders. Then spend the rest of your life messing with the possibilities. By the way, that's why I said aim high if the grouping is good. |
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I will do that then, I will make some up that vary OAL with 4.1-4.2g of TG I looked at the specs and will go with 1.135 1.140 1.145 1.150 I already have tried 1.155, after that I will see if there is any difference and pick the best, how many of each should I make I was thinking 5 rounds |
My belief is because it's faster and out the barrel before you're getting much effect of recoil that lifts your muzzle up. A heavier bullet moves slower and the gun starts rocking back before the bullet gets out of the muzzle. This pissed me off years ago, trying to figure out why a slower 180 grain load in a rifle printed higher than a faster 150 without touching the scope. Only thing that makes sense to me is the effect of recoil before the bullet exits. |
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I have over the past couple of days subjected myself to find the answer to OAL and I have figured out there is no correct answer it is all subjective. My Speer Manual says load to a OAL of 1.135 with a Speer TMJ RN 124g I currently am using Winchester 124 RN, I know that if the bullet is seated to deep (below 1.135) it can cause pressure problems and the max is 1.169 which may not chamber so I will play around in the middle and as far as powder charges it's about as elusive as OAL the book says 4.0-4.4g of TiteGroup I will most likely settle on 4.1-4.2 as it has been reported that the small difference won't affect POA vs POI I am going to the upcoming Indy 1500 and get some PowerPistol to try as it comes with positive reports for the 9mm Like I said I am very, very new to reloading and maybe I am making to much out of this but I find it of great interest to find the most accurate round for my 9mm but I also have to remember that with a 3" barrel and carrying for defense I won't be at 50' either so if it shoots low at 21' maybe I should go with a heavier round or aim higher using the 124 
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I've got a topic running right now about handloads shooting high. here The sierra manual says that faster loads shoot lower so you would have to reduce powder charge. I got the opposite results but that was with a .45 which is a lower velocity round. I think that in the .45 with such low velocity, muzzle flip has more to do with point of impact so increasing the charge, and thus increasing muzzle flip, raises point of impact. However, with the 9mm this may be the opposite. I would load up some reduced loads in decreasing increments down to the minimum load and see how point of impact is affected. No matter what, never exceed maximum loads. I would be interested to see what results you get. BTW, when working up my 9mm load I got lucky with 4.0gr of titegroup behind a 115gr fmj at 1.160" OAL. POI in line with sigts on my glock 19 an no further adjustment needed. May work for you as well. Good luck and be safe. |
| Just a thought and please dont be insulted but you did say that they were low and left. Classic trigger control problem. I recently started jerking the trigger for some reason and was shooting low and left. Trying to work on trigger control and flinching problem now. It happens to the most people at some time. Maybe the reloads just made it show up more. |
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Got back from the range today with my reloads of varying OAL (1.140-1.160) the rounds that were at the lower OAL actually shot pretty well and grouped pretty well I see where some have seated a 9mm round to around 1.050-1.1 my Speer manual gives a min of 1.135 but it's for a Speer bullet so I will ask can I go lower on OAL I am set at 4.1g of TG with a Win bullet and a CCI 500 primer |
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