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+--- Thread: Restarting load development (/showthread.php?tid=664)
Restarting load development - r.tenorio671 - 05-28-2022
...about to restart my load development now that (1) I have sufficient LVR (2) my barrel has ~150+ rounds thru it. I also picked up a 500qty box of 107 SMK's. I pressure tested them up to 29.1 gns and all looked good. I also received my MagnetoSpeed V3 which should allow better/easier capture of data from my old CHRONY Beta that I clipped on my last outing to pressure test the SMK's. One thing I'm going to change is to load to COAL's recommended by the Berger, Hornady & Hodgdon data for the specific bullets I have. Most of the heavies call for the 2.260" COAL, but lighter projectile's vary.
....I'll post my results if anything worthy shows up, good or bad. To be honest, so far my results have been pretty much similar to what others have posted. Due my location, my temps average 85F/60-85%RH year round so it may be helpful for folks developing their summer loads.....maybe.
RE: Restarting load development - grayfox - 05-28-2022
All good things. As to Coal's I found even a couple of mfr OAL's can be too long for a given real world chamber, so don't forget to chamber test your own for the distance to lands.
IIRC this happens more with the non-secant ogive bullets.
RE: Restarting load development - Dino11 - 05-29-2022
Here is a good read for you, their are links in this article to other very good reloading educational tutorials.
The information is factual and proven on some specialized equipment, it will give you a whole new perspective on the way you reload.
Mark is a very renowned precision rifle builder and is a very smart guy, I have had the opportunity to spend some time with him and learned a thing or two.
https://precisionrifleblog.com/2020/04/15/18-shot-bullet-jump-challenge/
https://precisionrifleblog.com/2020/03/29/bullet-jump-load-development/
RE: Restarting load development - r.tenorio671 - 05-29-2022
(05-29-2022, 10:03 AM)Dino11 Wrote: Here is a good read for you, their are links in this article to other very good reloading educational tutorials.
The information is factual and proven on some specialized equipment, it will give you a whole new perspective on the way you reload.
Mark is a very renowned precision rifle builder and is a very smart guy, I have had the opportunity to spend some time with him and learned a thing or two.
https://precisionrifleblog.com/2020/04/15/18-shot-bullet-jump-challenge/
https://precisionrifleblog.com/2020/03/29/bullet-jump-load-development/
...thanks Dino, I've read both of those articles previously, lots of good info in them, some of which I've explored in the past. TBH, as a purely recreational shooter and only using gassers, the magazine dimensions are the greatest influence on limitations. Granted, folks have developed multiple workarounds such as windowing, etc., but those may induce new factors.
....my "focus" leans more to making my loads that stay within the confines imposed by the equipment's dimensions. This is more relevant to me since my component supply is quite limited and not easily replenished. As close to "absolute reliability" is my primary objective. Enhanced accuracy, higher FPS, etc. are secondary, but not at the expense of reliability. That attitude was borne out of my military career and was really reinforced by my Afghanistan deployment. As much as I enjoy making "bug holes", "minute of man" is my absolute minimum standard, which is also quite sufficient for the majority of 4-legged game in my locale as a food source.
...when I post my results, it's not meant to try and convince anyone to adopt or that it's the "better way", but a simple sharing of experiences which may or may not benefit someone.
....enjoy the upcoming 3 day weekend, Monday being a day many of us are thankful to be enjoying as we reflect on the gift given us by our brothers and sisters who are not here to enjoy their sacrifice.
RE: Restarting load development - Dino11 - 05-29-2022
If you are using metal mags some of them let you load COAL as long as 2.300. Most of my AR 6 mm ARC's are loaded to 2.295 giving me about .055 to .060 off the lands on most of my gasser stuff using secant olgive bulletts. These bullets have a long slender profile to them and tend to have large jumps. Now if you take the Hornady 105 and compare it to a Noster or Berger 105 you will see what I'm talking about. You have to load the Hornady at no more than 2.200 to 2.220 or you will push it into the lands.
RE: Restarting load development - r.tenorio671 - 05-29-2022
(05-29-2022, 08:40 PM)Dino11 Wrote: If you are using metal mags some of them let you load COAL as long as 2.300. Most of my AR 6 mm ARC's are loaded to 2.295 giving me about .055 to .060 off the lands on most of my gasser stuff using secant olgive bulletts. These bullets have a long slender profile to them and tend to have large jumps. Now if you take the Hornady 105 and compare it to a Noster or Berger 105 you will see what I'm talking about. You have to load the Hornady at no more than 2.200 to 2.220 or you will push it into the lands.
....true, bullet ogive does make a difference. In my barrel the Berger 95 Classic Hunter (hybrid) -vs- the Berger 95 VLD Tgt (secant), there is a 0.1313125" difference in their "touch point" when COAL is measured (2.197" -vs- 2.328") and thier CBTO's were 1.730" -vs- 1.726" respectively.
I found the articles you referenced to be interesting and enlightening on the common findings of large jumps, especially since the SAAMI chamber drawing indicates that there would be a 0.0899" freebore length in a SAAMI compliant chamber. Buying an off the shelf/online barrel makes how exact that dimension is somewhat of a "spin the wheel" prospect.
...large jumps will be the default in gassers, IMHO, only because of the SAAMI freebore spec AND the 2.260" 'standard' for magazines, regardless if a particular mag brand/model gives a little more room. I've seen enough posts in multiple forums where folks encountered feed issues when they exceeded the 2.260" COAL, be it the COAL or influenced by other factors (feed ramp, mag fit/height, etc.). It was more prevalent in "mix & match" of upper and lower brands.
...I want to simplify my reloading process so I'll stay within the 2.260 limitation and work the powder charge and minor negative seating depths to find the widest "forgiveness" band. Since I picked up 500 107 SMK's, those will be my focus for the time being.
RE: Restarting load development - Dino11 - 05-30-2022
I have not had a single issue loading to 2.295 with Berger and Nosler bullets, But as you stated that might not always be the case for every rifle. Between my son and I we have had 10 6 ARC rifles gas guns and bolt action that passed through my hands, a couple of them were sold off but the majority of tn them are in his and my safes.
Now I do load the light bullets on the short side, but very rarely shoot them, I don't know why I have a shit ton of them in my arsenal to load up. And some of them are very accurate out to about 400 maybe 500 yards on a calm day. Not only that they scream 3000+ FPS so flight time is greatly reduced.