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BoatTail
Well-Known Member
I started doing load development for my 28 Nosler and need some help interpreting the data. So here is some background Information:
Cartridge: 28 Nosler
Rifle: Borden Custom Rifle with an Alpine Magnum Action
Barrel: 26 inch, Hart #3, 1 in 9, Fluted with a Muzzle Break
Case: 26 Nosler necked up to 28 Nosler
Powder: Hodgdon H1000
Bullet: Nosler Accubond LR 7mm 175grs
OAL: 3.51 with the 175 ABLR's.
Temp: 70 Degrees
Elevation: ~5000ft
Loads started at 79grs of H1000 in increments of 1 gr to 83 and then by ½ gr to 87. Basis for the loads were from info gathered from Quick Load.
When I finished the Range Officer at my range asked me if there were any surprises. I was surprised that none of the rounds produced a sticky bolt. Number 13 should have in my view. The primer was flattened and the Plunger circle clearly shown with a faint extractor outline.
I did the load testing in a pistol house with limited light so did not see the plunger marks until I got home. Had I seen them I would have likely stopped at load 9 or 10. The picture below is of the fired cases #8, 9 & 10 left to right on the top row and #11, 12, & 13 right to left on the bottom row. Plunger marks can be seen on the bottom of the case head. I'll resize and punch the primers out and see if #13's primer pocket has expanded as I suspect.
What I need help with is interpreting the Case Head expansion data. I did not have my micrometer at the range and so checked these afterwards. I know I should have marked, measured, fired and then measured each one but was doing this from memory and mistakenly thought I could measure later based off a standard average unfired case size. It's been a while since I used a micrometer so I'm hoping I measured right.
In any case I'm wondering if the standard Magnum maximums of .0006"-.0007" expansion is where the maximum pressure is holds here. Since the case sizes are so much smaller than the SAAMI Case dimensions. Or if I should be using some other base size. My thoughts are that 83.5grs may be the sweet spot. I think I'm luck I did not have an incident with #13 load but again was surprised I did not see a sticky bolt. Live and learn!
Your thoughts?
Here is the Load data and case head picture of the #8 - 13 loads:
Cartridge: 28 Nosler
Rifle: Borden Custom Rifle with an Alpine Magnum Action
Barrel: 26 inch, Hart #3, 1 in 9, Fluted with a Muzzle Break
Case: 26 Nosler necked up to 28 Nosler
Powder: Hodgdon H1000
Bullet: Nosler Accubond LR 7mm 175grs
OAL: 3.51 with the 175 ABLR's.
Temp: 70 Degrees
Elevation: ~5000ft
Loads started at 79grs of H1000 in increments of 1 gr to 83 and then by ½ gr to 87. Basis for the loads were from info gathered from Quick Load.
When I finished the Range Officer at my range asked me if there were any surprises. I was surprised that none of the rounds produced a sticky bolt. Number 13 should have in my view. The primer was flattened and the Plunger circle clearly shown with a faint extractor outline.
I did the load testing in a pistol house with limited light so did not see the plunger marks until I got home. Had I seen them I would have likely stopped at load 9 or 10. The picture below is of the fired cases #8, 9 & 10 left to right on the top row and #11, 12, & 13 right to left on the bottom row. Plunger marks can be seen on the bottom of the case head. I'll resize and punch the primers out and see if #13's primer pocket has expanded as I suspect.
What I need help with is interpreting the Case Head expansion data. I did not have my micrometer at the range and so checked these afterwards. I know I should have marked, measured, fired and then measured each one but was doing this from memory and mistakenly thought I could measure later based off a standard average unfired case size. It's been a while since I used a micrometer so I'm hoping I measured right.
In any case I'm wondering if the standard Magnum maximums of .0006"-.0007" expansion is where the maximum pressure is holds here. Since the case sizes are so much smaller than the SAAMI Case dimensions. Or if I should be using some other base size. My thoughts are that 83.5grs may be the sweet spot. I think I'm luck I did not have an incident with #13 load but again was surprised I did not see a sticky bolt. Live and learn!
Your thoughts?
Here is the Load data and case head picture of the #8 - 13 loads:
Attachments
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BoatTail
Well-Known Member
With no responses I decided to do accuracy testing with the 83 and 83.5 gr loads of H1000. I also ordered some Retumbo power and will be testing the following load data from Rifle Magazine:
BoatTail
Well-Known Member
I have completed my load work and testing with with the 28 Nosler using Hodgdon's Retumbo and H1000 and topping it with Nosler Accubond Long Range 175 gr bullets 50 thousands off the lands.
The Retumbo loads were 83 and 83.5 grains respectively. Velocities were inconstant and group sizes stretched to 2.25 and 1.375 inches respectively at 100 yards.
With the H1000 loads of 83 and 83.5 grains the rifle is however is shooting nice little 0.375 inch groups at 100 yards. Muzzle velocity averaged 3162 and 3186 FPS respectively.
Honestly this was a surprise to me as I thought the Retumbo loading would be the one I would go with. Perhaps with a different rifle or additional load configuration work it could be. However the accuracy and velocity I'm getting with the H1000 load configuration is very good with this rifle so I will be sticking with it.
Next I will be sighting in for 200 yards, creating drop chart data, and going out into the field to test it out to 800 yards.
The Retumbo loads were 83 and 83.5 grains respectively. Velocities were inconstant and group sizes stretched to 2.25 and 1.375 inches respectively at 100 yards.
With the H1000 loads of 83 and 83.5 grains the rifle is however is shooting nice little 0.375 inch groups at 100 yards. Muzzle velocity averaged 3162 and 3186 FPS respectively.
Honestly this was a surprise to me as I thought the Retumbo loading would be the one I would go with. Perhaps with a different rifle or additional load configuration work it could be. However the accuracy and velocity I'm getting with the H1000 load configuration is very good with this rifle so I will be sticking with it.
Next I will be sighting in for 200 yards, creating drop chart data, and going out into the field to test it out to 800 yards.
chuckhammer
Well-Known Member
I have found Retumbo to be overly fast burning in a wildcat of mine that is similar to 28 Nosler in case capacity when shooting 180s. Had much better luck with Reloader 33. I bet 88-89 grains of RL33 would take you to 3300 or so, assuming your bbl is 28". Not sure how long your primer pockets would stay tight as Nosler brass is fairly soft to my knowledge.
Edit - I see your bbl is 26" but since these are 175s rather than 180s I bet you can still get close to 3300 with RL33.
Edit - I see your bbl is 26" but since these are 175s rather than 180s I bet you can still get close to 3300 with RL33.
Dick Tinsley
Well-Known Member
Good data on here. I to think I'll start with H-1000! Good work guys!!!
DT
DT
BoatTail
Well-Known Member
I spoke to Nosler today, their reloading group and found out they are close to releasing their load data for the 28 Nosler. The individual I talked to had notes on the loads from a meeting earlier in the day. They would be releasing them this week but the person that has the final say on the load data is on vacation this week so he said it may be next week before it is released. In any case he gave me some of the load data over the phone so I'm passing it on to you. Note that this is unofficial data and there is always the possibility I could have written it down wrong but this is what I have:
POWDER GRS FPS
H1000 79 3100
RL33 88 3200
RL25 78 3100
Retumbo 83 3200
He also read off US869 with a velocity of 3200 fps but I wrote down 92 grs and it seems high so wait for the official data for all the loads.
I asked him about the H1000 that the load and the velocity seemed low. He said that when they tested the H1000, and went up to 80 grs the pressures rose to 67,000 psi so 79 was the max there.
You will remember that my test load that I was going to go with was 83.5 grs of H1000 with a velocity of 3186. Sounds like I may be a little over pressure limits, but without a gauge it is hard to tell. I'm going to order some Reloader 33 and do some load testing with it.
POWDER GRS FPS
H1000 79 3100
RL33 88 3200
RL25 78 3100
Retumbo 83 3200
He also read off US869 with a velocity of 3200 fps but I wrote down 92 grs and it seems high so wait for the official data for all the loads.
I asked him about the H1000 that the load and the velocity seemed low. He said that when they tested the H1000, and went up to 80 grs the pressures rose to 67,000 psi so 79 was the max there.
You will remember that my test load that I was going to go with was 83.5 grs of H1000 with a velocity of 3186. Sounds like I may be a little over pressure limits, but without a gauge it is hard to tell. I'm going to order some Reloader 33 and do some load testing with it.
BoatTail
Well-Known Member
chuckhammer,
You mentioned we should be using RL 33 at 88 to 89 grs for a velocity of 3300 fps in a longer barrel in a wildcat similar to the 28 Nosler. Sounds like you may be onto something. Can you tell me what your accuracy like and what is your load configuration is?
Bruce
You mentioned we should be using RL 33 at 88 to 89 grs for a velocity of 3300 fps in a longer barrel in a wildcat similar to the 28 Nosler. Sounds like you may be onto something. Can you tell me what your accuracy like and what is your load configuration is?
Bruce
chuckhammer
Well-Known Member
Bruce,
My wildcat is an improved 7-300 Win Mag I call the 7mm Valkyrie. The body taper is reduced by about .009" at the shoulder and the shoulder angle is increased from 25 to 37 degrees. The goal is to neck size only and eliminate case growth and trimming. In a fired WW Super case this yields a measured capacity of 93 grains H20 to the case mouth. Norma brass will hold more but is fairly thin and soft by comparison, thus limiting max pressure.
My rifle is built on a Savage 110 with a 28" barrel, 1" diameter straight taper, 1/9 twist Criterion Match. Using 86-87 grains of Reloader 33 behind a Berger 180 Hybrid ignited by a Russian LRM primer in the above mentioned WW Super brass with a ~3.770" COL (2.950" base-to-ogive) I'm getting 3250-3300 fps. This is a max++ load as it leaves slight ejector marks on the case head and somewhat flattened/cratered primers. In all likelihood this load is running 68-70k psi max pressure. Primer pockets are still tight (enough) after 3 firings.
I've only fired 50 total rounds down this barrel using various powders and bullets so load development for accuracy is incomplete. However, the above load has given me right at 1 MOA at 100 yards for five consecutive shots. This is using my humble SWFA SS 16x50 fixed power scope and fired from the bench off of a Caldwell "7 Rest."
My above experiences are how I based my 88-89 grain RL33 suggestion for the 28 Nosler. I understand this case has something like 100 grains H2O capacity.
My wildcat is an improved 7-300 Win Mag I call the 7mm Valkyrie. The body taper is reduced by about .009" at the shoulder and the shoulder angle is increased from 25 to 37 degrees. The goal is to neck size only and eliminate case growth and trimming. In a fired WW Super case this yields a measured capacity of 93 grains H20 to the case mouth. Norma brass will hold more but is fairly thin and soft by comparison, thus limiting max pressure.
My rifle is built on a Savage 110 with a 28" barrel, 1" diameter straight taper, 1/9 twist Criterion Match. Using 86-87 grains of Reloader 33 behind a Berger 180 Hybrid ignited by a Russian LRM primer in the above mentioned WW Super brass with a ~3.770" COL (2.950" base-to-ogive) I'm getting 3250-3300 fps. This is a max++ load as it leaves slight ejector marks on the case head and somewhat flattened/cratered primers. In all likelihood this load is running 68-70k psi max pressure. Primer pockets are still tight (enough) after 3 firings.
I've only fired 50 total rounds down this barrel using various powders and bullets so load development for accuracy is incomplete. However, the above load has given me right at 1 MOA at 100 yards for five consecutive shots. This is using my humble SWFA SS 16x50 fixed power scope and fired from the bench off of a Caldwell "7 Rest."
My above experiences are how I based my 88-89 grain RL33 suggestion for the 28 Nosler. I understand this case has something like 100 grains H2O capacity.
bspooley,
Do you happen to know what bullet (grains) they were shooting for these numbers?
Thanks
BoatTail
Well-Known Member
Sorry forgot to provide that info. It was the 7mm 175gr Nosler Accubond Long Range bullet.
I'm getting ready to order a 28 Nosler reamer. I was just wondering what reamer is everyone using. Are you guys just using the 28 Nosler SAAMI reamer available from PT&G? Are you custom throating your rigs or does the C.O.A.L. come out about right with the SAAMI reamer when using the 175 grain LR Accubonds? Thanks in advance for your replies. I'm encouraged by the results reported here and am looking forward to this build.
D
Deleted member 46119
Guest
I used the PTG SAMMI spec. I think there is .000 throat. It would take me a bit to find the reamer print but it is marked as submitted by Nosler.
BoatTail
Well-Known Member
I used the 28 Nosler SAAMI reamer from PT&G and have attached the drawing below. Prior to it's release, I was working with PT&G on a custom version and honestly was struggling with the throat length. I wanted to use the full length of the neck, fit inside the magazine box appropriately and not infringe too much on the powder. As it turns out just before I pulled the trigger on my custom reamer the guy with PT&G told me he worked with Nosler and had an official SAAMI version and sent me the drawings. I did some quick calculations and it looked about right so ordered it instead.
What I have found is the throat with the SAAMI version is perfect for the 175 grain Accubond LR's. The bullet seats so that the boattail is just below the neck giving full use of the shorter neck yet it fits nicely in the magazine box. COAL in my rifle, which used the standard SAAMI Reamer, is 3.51 with the bullet 50 thousands off the lands. As you may have read ABLR's like to be off the lands a bit (they need a little running room) for best accuracy.
COAL in my rifle for 180 grain Berger VLD's should be about 3.573 with the bullet 15 thousands off the lands. However I have not loaded or fired any of these preferring to go with the ABLR's.
I don't think you can go wrong with the 28 Nosler. It's fast, has a lot of downrange energy, is accurate with the right barrel and just looks really good. Get a good muzzle break and wear hearing protection though. The break on mine really tames the recoil on this very powerful cartridge. Make sure you validate my suggested COAL in your rifle before using.
Good Luck!
