Did a little shooting today, with my custom springfield,.257 roberts. Rifle is a very acurate rifle and I decided to take a few of the better loads acuracy wise and chrony them.
While most of the loads gave reasnoable velcity I was sadly suprised that the load I had best hopes for , a 110 grain nosler acubond over 42 grains of IMR-4350 only gave 2575 and 2642. I was expecting somthing clase to 2900.
I saved 1 round and brought it home to pull the bullet and weigh the charge and 42 grains right on the nose.
anyone heard of a bad lot of IMR-4350 ?
Really dissapointing as this load gave me 3 into .30 inches and a 4th to.70.
Not really a problem beacuse a 100 grain sierra over IMR-4064 gave 2950 2 holes touching and a 3rd to an evean inch.
I will boost the sierra 4064 load a half grain but I am reluctant to fool; around with the 4350 load much, as my rifle is a low numberd springfield and I thik I would need a lot more powder to get close to what I want.
I think I will try the acubond with H-4350 RL=19 and IMR-4064.
Mabye a tech at IMR will have an Idea for me.
I like at least 3000 with a 100 grainer and close to that with a 110.
Any Ideas why the IMR-4350 Load would be so slow ? the nosler book gives 2800 with a 115 grain bullet same charge?
...tj3006

Slower than normal lot of IMR4350? How was the pressure? Was the shoulder sooted up? You may have a mislabeled can of 7828.

How old is the barrel?

Jaywalker

I think you had your hopes a little high...I would expect that load to give around 2700 fps at 15'.

I did a little double checking,
And the load from Nosler was 40 grains even for a 115 grain bullet for 2800 FPS, Well my 24 inch new douglas barrel only gave about a 2600 FPS avarage with 42 grains and a 110 grain bullet.
I looked at some of my other manusals and my speer shows 43 grains with a 120 grain bullet for 2759 fps my Barnes has 43 for 2752 with a 115 and my old Hornady has 42 grain with a rounded of figure of 2800 with a 120.
and the IMR web site shows 41.5 grs witha sierra 120 giving 2700+ and only 4500 CUP, and my smith and I agree that a 50,000 Fps load should be safe in my rifle.
SO, it looks to me like the culprit lies in the nosler DATA, they must just be using a test barrel or rifle that has a fast barrel and or generates high preasures with lo powder charges.
I think I will up my charge to 43, 1 full grain with the 110 grain pill, I should still be quite safe, chroney that load if it seems apropriate go up half grain at a time, ...tj3006

Tom:

Just so you'll know. Slug the barrel w/soft lead and mic it and the bullets, compare. Might not be getting a good seal.

How old is the powder?

www.imr.com

Amazing what we relearn after getting a chronograph ain't it?? Whole different deal than what we thought it was. At least that's what I learned.

Wasn't near as smart as I thought I was.

George

I once loaded a friends 22-250 to the recipe printed from Hodgdon.....I used BL-C(2) because I had it and it seemed to work fine even though it's a bit fast for the 22-250

We went dog shooting and the 22-250 just didn't have the range it formerly had in the past so we chronographed the load (a lot too late) and the velocity was a full 400'/sec slower than the Hodgdon data called for.....

I will never know what caused such a large discrepancy in the performnce but it was there.....I'll not use that powder for the 22-250 again.....not sure this helps you but performance isn't always what the book says it should be.....

Just because a recipe says it will give a certain performance it's not always the case.

The 4350 you describe should have performed better....I agree.... Some things we accept and move on.....but IMR 4350 is not a bad choice for that cartridge.....in my case I picked a poor powder.

After looking into this a little deeeper. I have come to the conclusion that my load is just too light. I have found in other manuals 120 grain bullets with the same charge at least, as my 110 grain nosler. It could be that nosler just had a fast barrel or somthing in that ball park.
I am going to go with 43 grains and chroney again, I will up the load with my sierra 100 gr boat tail too , That was 40 grains of IMR-4064, I,ll only bump that a Half grain, as I am near the velocity I want now. Don't think I want to push the sierra bullet much over 3000,
I tried H-414, my other Roberts loves it with a 100 grain tripple shock, but I did ,nt have much luck, Gonna try some RL-19 too I think.
...tj3006

Reloader-19 is way too slow burning for your application. H-4350 is too slow. H-414 is too quick, as is IMR-4064. Get Quickload and play around with loads that give you good load density, powder combustion and pressure. It will pay for itself in what you'll save in wasted time and components. Per QL, IMR-4831 is perfect.

Sometimes the nuzzle blast from a slow (for caliber) powdew will upset the chronograph.
Back away another 10 feet and try again. In my Krag with 4350 I can gain 200 fps by backing away.
Good Luck!

quote:

Originally posted by Ralph Hyrlik:
Reloader-19 is way too slow burning for your application. H-4350 is too slow. H-414 is too quick, as is IMR-4064. Per QL, IMR-4831 is perfect.

So, RL-19 is "way too slow", but the similar or slightly slower burning IMR-4831 "is perfect"?
I'm afraid the poster has his numbers mixed up somewhere.

It's been years since I loaded for a .257 Roberts, but 3200 fps with a 100 grain bullet and 2950 FPS with a 117 grain bullet were typical velocities with surplus 4831 (slower than either RL-19 or IMR-4831). Surplus 4831 also did well with bullets as light as 90 grains. This was in a 23.5 inch barrel. Pressures were "normal" for a "high intensity" cartridge, ie. roughly equal to those that the .270 and similar cartridges are normally loaded to.

If you have a low-numbered Springfield you need to have the receiver hardness tested. The brittle steel of improperly heat treated Springfield receivers can let go, even with loads held to 45,000 CPU. If your receiver is okay, then there's no reason not to load the Roberts as you would any other cartridge on the '06 case head.

Ralph hyrlik-I would say you have H-4350 and imr 4831 mixed up.