Looking for some advice about reloading cast bullets for .303 british

I'm hoping to tap into the wealth of knowledge on this website and solve this accuracy, or lack of accuracy issue with cast bullets for .303 British.
Because of the lack of jacketed "factory" projectiles for .303 BRT, I started getting into casting my own.

I am casting a .311 RN bullet tht's 174 grains (Gas checked and lubed).
I load it with 25 grains IMR 4227.
O.A.L" 2.930" (as per Lyman 49th edtion but their listing the 200gr bullet)

At fifty yards my target looks like a high school dance floor ( some on the right and some on the left) no real grouping.
Other "non" Enfield shooters that cast bullets were saying that I'm not seating the projectile deep enough but mine (like most Enfield rifles) have room to spare in the chamber.

Are there any "Cast" .303 shooters that would offer some advice please.

Not a 303br reloader but here is my advice
Diameter need to be bigger
IMR 4227 made in canada (On the label or made in the other place)

You are pushing velocity too fast
4227 does not burn well at lower pressure and is position sensitive with less than 80%+- of the case being filled
you cold go to a lower charge and use a dacron filler ---> but Unique is less work
Lyman Cast book # 4 has loads

Most of the good powders for cast have been discontinued "SR-4759"is one
2400 is another good powder

Look up a load for 303br and cast using Unique /internet or Lyman Cast book # 4 has loads
Unique burns well-- you use less = cheeper

if you want to hunt with cast find a heaver bullet 200g

with cast if you go to fast for your barrel twist you will get larger groups

Aol Do not worry about it so much
Try to keep gas check in the neck of the case --you can go deeper --some cases are loaded very deep -->see 300 aac blackout -247g cast
 
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4227 does not burn well at lower pressure and is position sensitive with less than 80%+- of the case being filled
you cold go to a lower charge and use a dacron filler ---> but Unique is less work
I've not found this to be true. I've used IMR4227 down to 30% load density without any problems in rifle cartridges. I don't use it too often because there are other powders I have more success with but I haven't had any issues with low density loads of IMR4227.

H110/W296, that's another story all together. That powder burns best when compressed slightly and isn't really suitable for reduced loads. It's another common magnum pistol powder along with H and IMR 4227.

The only powder I've had issues with recently is H4198 when trying to produce black powder pressure loads (20-24k psi). It doesn't want to burn well down that far.

Most of the good powders for cast have been discontinued "SR-4759"is one
What other powders other than the SR's have been discontinued? There are many good powders for cast bullet shooting and I'd hardly call the discontinuation of two powders (SR-7625 and SR-4759) to be "most" powders that are good for cast bullets. SR-4759 was one of my favourites and I loaded a lot of cast with it but I haven't had much problem replacing it in all my loads; just took time to develop all new loads for many rifles. I now use mostly H4198 for reduced rifle loads and Unique, Titrgroup, Longshot, 800X, Trail Boss, and others for very light loads.

Even the 60% rule with H4895 works well with cast bullets.

I've heard very good things aboute Accurate 5744 with cast bullets (supposed to be very close to SR-4759) but haven't found any to try myself.

SR-4759 was discontinued previously (in the 80's or 90's I believe?) and brought back. I'm hoping it happens again but if not, there are many other commonly available powders that work well.
 
Here's a pic of some of my terrible paper patched bullets. The wraps overlap which is a big no-no. They shot like buckshot out of a cylinder bore (4' group at 50yds).


I was in a hurry the night before going to the range and didn't notice until I had finished loading. I think I may have used patches meant for my 8mm loads. These were .309" cast that I PP'ed up to .317" or so. Was for a rifle with a terribly worn and pitted bore that slugs .316"ish.





Some successful loads I've used in the past:

For a No.4 Mk.1 that slugged .3138" (2-groove barrel)

200gr .314" GC'ed tumble lubed water dropped pure WW alloy
WW-Super brass
CCI LRP
23.0gr of H4198
QuickLoad showed ~1720fps but that's +/-10%; I never chronied them.

Same load with a .311" 185gr bullet also worked well with no leading which really surprised me. Maybe the 2-groove barrel pushed more lead from the lands into the grooves to prevent leading? Since it was a 2-groove barrel I was able to mic the slug to find the land diameter which was .3022". This rifle shoots jacketed .308" bullets accurately as well.




For a Martini-Enfield with a terribly pitted bore that slugs .3155" to .3160" (hard to measure since it's a 5-groove barrel).

187gr .3160" to .3165" as cast (not sized; thus the tolerance range), tumble lubed, rebated base for GC but none used, pure WW alloy
IVI brass (no date) as well as WRA (Winchester Repeating Arms?) 1953 dated surplus brass (the two different headstamps had almost identical weights so I mixed them in the same batch).
CCI LRP
1.9cc of Trail Boss (I use the Lee scoops for Trail Boss loads)
Quite light, still supersonic, and my records show groups down to 1.5" at 50yds off a bench (iron sights).

The paper patched loads that I messed up were also for this rifle.
 
Discontued powders
Here is the list:
SR4759
pyrodex pellets
Imr 4227 Made in Canada
IMR 7625
IMR 4007
IMR PB
Winchester Supreme 780
Winchester AA Lite

and others
 
Discontued powders
Here is the list:
SR4759
pyrodex pellets
Imr 4227 Made in Canada
IMR 7625
IMR 4007
IMR PB
Winchester Supreme 780
Winchester AA Lite

and others

I wasn't aware IMR4227 wasn't made in Canada anymore. My last bottle from a few months ago still says made in Canada but maybe it's old stock.
A quick Google search show they discontinued H4227 and kept IMR4227 but it's now made by ADI like many Hodgdon brand powders. So that would mean the new IMR4227 is the same as the old H4227 but they discontinued the true IMR4227. Odd. They're so close in burn rate they are practically interchangeable from starting loads with proper load development so I don't see how it can truly be said to be lost.
I'm surprised it's still under the IMR label as when they swapped all their flake powders from the General Dynamics plant in Quebec they changed the bottle labels to Hodgdon instead of IMR. 700X, 800X, and Trail Boss are now under the Hodgdon banner instead of IMR. I don't know where those are being made now. Rumour was several bulk shipments from GD were rejected for being way too far off in burn rate and Hodgdon gave up contracting any flake powders from them. The stick powders they discontinued were mostly for lack of popularity.

Pyrodex pellets being discontinued is news to me. I found forum discussions from Jan 2014 talking about it but they're still in stock everywhere I look. It's all most stores around here carry for muzzle loaders and there's loads of them available. Is this all two year old stock or did they bring them back?

IMR 4007 and Win 780 seem much too slow to be used for cast bullet loading so I don't see how that applies to this.

IMR PB, SR-4759, SR-4756, and SR-7625 are all regrettable if people had excellent loads worked up for them but they are hardly irreplaceable. I have numerous loads for SR-4759 and SR-7625 that I found it quite easy to replace with a little load development with close powders.

Never knew anyone who use Win AA Lite. There's loads of shotgun data for it but it seems maybe a little too fast for cast bullet loading. Even Reddot for me seems far more picky than slower flake powders like Unique, 800X, Bluedot, and others.

It's all beside the point. There are so many other powders available that work wonders for cast bullet reloading. From my shelf alone I'm looking at IMR4227 (regardless of if it's Canadian or not), 800x, Unique, Bluedot, Longshot, Titegroup, H4198, H4895, IMR4198, IMR4895, Benchmark, IMR3031, HS-6, and Trail Boss (and my last remnants of SR-4759 and SR-7625). That's just what I have on hand, there are many more available that also work great for cast everywhere from extra light gallery loads up to the upper limits for cast bullets. To say that "most of the good powders for cast have been discontinued" seems like a gross exaggeration.
 
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