Post by picklehead on Apr 27, 2019 21:16:44 GMT -5
I made some very good notes today on the 28 Nosler and Horn brass. Brand new case is .546 at the web or the way I measured them. Done this 6 times on 5 differ cases. Since I have seen that I can push the rifle harder with this brass,, I wanted to step it up a bit. 86 grains of R33 was my load with the Nosler brass and thicker necks / some bullet run out. I made it up to 88 grains today and still have room to ease up .3 or more. .546 stayed .546 and never changed as I climbed up the ladder. I had a half sticky bolt twice and the neck wall thickness is to blame for it. No double ejector marks on the case heads at all. Normal crater on the primer as always and cases stayed at trim length other than one but may have not had it perfect to start with.
I was getting .303 with sized neck and .305 with bullet seated so that's great. Cases with .0006 of difference in neck wall, will bump pressures up like you dumped 3 grains more of powder in them. Not sure if im making sense of this but it is true. The rifle has a very tight spec chamber and will shoot like hell if all brass is perfect. It printed a .345 group at 220 yards with four cases that came in at 259.1 to 259.5 AND .0002 of run out. Cases that went 1 to 4 full grains differ in weight and lots of run out,, printed a constant 1 to 1.5 group. Powder charge didn't seem to matter either and 86.7 to 88 ,,, done the same. Im lost without my chrony and have no idea what increasing the charge .3 grains at a time is doing. 86 grains is 3152 with the 175gr SMK and know that from the past. 88 grains should be pushing the pill about 3250 to 3300 FPS but that is no fact at all and guessing from playing last year. I know im getting 50 FPS more than what Nosler claims for their data on every .5 grains and that's great. I just don't know if ive topped out at 88 or if it is still climbing 38 to 50 FPS,, for each half grain increase. No need to keep going until pressure signs show up and only get a extra 10 FPS with a full grain. That's just adding to throat erosion for nothing.
I could care less about 3300 FPS and that's why the rifle has a 20 MOA rail and good scope on it. Amazing how .0005 or so of neck thickness can shut you down at 78 grains of powder but 88 is fine with a proper prepped case. I used 78 for an example and well below MIN charge by all listed data and it happened to me last year when using the Nosler brass,, UNTIL WE FIGURED IT OUT. Yes, WE and it was figured out on here. Im not knocking Nosler brass and it is some good stuff. Just my chamber and necks has to be turned in NOSLER or Hornady to get the best out of it and keep pressures where they should be. Nosler brass was hands down more consistent in weight, trim length and flash holes,,, COMPARED TO THE HORNADY. The weight differ can be over looked and its all about internal case volume and concentricity. I could feel the differ in neck tension when seating the bullets in cases that was differ in neck wall thickness. Could damn sure see it on paper too! 1.25 inch differ and know I did my part of shooting the rifle. I also marked the cases that had run out over .0002 and it showed up fast on paper and pressures. Pressures didn't go through the roof but could tell on bolt lift and uneven carbon / heat signs on the necks. One side would be like a good seal should be and the other side was half blackened.
You can also see the differ on the clean necks when painting black and running into the die or chamber of the rifle,,, after fireforming. High and low spots of marker removed. The .345 group was done with four very well prepped cases and set my FLS die high and sized 3/4 of the neck / touched the case body,, barely. Shoulder was never touched and this doesn't happen all the time when using a FLS die as a neck / body die. Very few rifles that I own can be done this way and 96 % of the time,, the case will not chamber / headspace is way to long on the case. Sloppy chambers and brass swells out to much for just sizing the neck and barely touching the body. You know you have a tight spec chamber when you can size a fired case with two fingers on the press handle. Not 100% true but takes much less effort compared to sizing a 30-06 case that has been fired in something like a 742 rem or such.
I was getting .303 with sized neck and .305 with bullet seated so that's great. Cases with .0006 of difference in neck wall, will bump pressures up like you dumped 3 grains more of powder in them. Not sure if im making sense of this but it is true. The rifle has a very tight spec chamber and will shoot like hell if all brass is perfect. It printed a .345 group at 220 yards with four cases that came in at 259.1 to 259.5 AND .0002 of run out. Cases that went 1 to 4 full grains differ in weight and lots of run out,, printed a constant 1 to 1.5 group. Powder charge didn't seem to matter either and 86.7 to 88 ,,, done the same. Im lost without my chrony and have no idea what increasing the charge .3 grains at a time is doing. 86 grains is 3152 with the 175gr SMK and know that from the past. 88 grains should be pushing the pill about 3250 to 3300 FPS but that is no fact at all and guessing from playing last year. I know im getting 50 FPS more than what Nosler claims for their data on every .5 grains and that's great. I just don't know if ive topped out at 88 or if it is still climbing 38 to 50 FPS,, for each half grain increase. No need to keep going until pressure signs show up and only get a extra 10 FPS with a full grain. That's just adding to throat erosion for nothing.
I could care less about 3300 FPS and that's why the rifle has a 20 MOA rail and good scope on it. Amazing how .0005 or so of neck thickness can shut you down at 78 grains of powder but 88 is fine with a proper prepped case. I used 78 for an example and well below MIN charge by all listed data and it happened to me last year when using the Nosler brass,, UNTIL WE FIGURED IT OUT. Yes, WE and it was figured out on here. Im not knocking Nosler brass and it is some good stuff. Just my chamber and necks has to be turned in NOSLER or Hornady to get the best out of it and keep pressures where they should be. Nosler brass was hands down more consistent in weight, trim length and flash holes,,, COMPARED TO THE HORNADY. The weight differ can be over looked and its all about internal case volume and concentricity. I could feel the differ in neck tension when seating the bullets in cases that was differ in neck wall thickness. Could damn sure see it on paper too! 1.25 inch differ and know I did my part of shooting the rifle. I also marked the cases that had run out over .0002 and it showed up fast on paper and pressures. Pressures didn't go through the roof but could tell on bolt lift and uneven carbon / heat signs on the necks. One side would be like a good seal should be and the other side was half blackened.
You can also see the differ on the clean necks when painting black and running into the die or chamber of the rifle,,, after fireforming. High and low spots of marker removed. The .345 group was done with four very well prepped cases and set my FLS die high and sized 3/4 of the neck / touched the case body,, barely. Shoulder was never touched and this doesn't happen all the time when using a FLS die as a neck / body die. Very few rifles that I own can be done this way and 96 % of the time,, the case will not chamber / headspace is way to long on the case. Sloppy chambers and brass swells out to much for just sizing the neck and barely touching the body. You know you have a tight spec chamber when you can size a fired case with two fingers on the press handle. Not 100% true but takes much less effort compared to sizing a 30-06 case that has been fired in something like a 742 rem or such.