Hello, I was loading 14 grains of 4759 in a 30-30 CPA shooting a 178 grain bullet, breach seated. It’s been a few years since I have shot this barrel and with 4758 being discontinued it’s time to switch and was wondering where to start with using 4227 or 300-MP
Thanks
Wade

Thank you Jeff!

Burn charts inconsistent which one is faster, my experience 4759 and 4227 burn rates are nearly identical. Other day practice 200 yards offhand used both. 38/55 245 gr fixed bullet. Some loaded 17 grs 4227 others loaded 17 grs 4759  

Point of Impact about 1 moa difference.  Have seen 4227 impact higher other times 4759 strikes higher. My opinion more difference lot to lot than one powder to the other.

My cast bullet 30/30 fixed load 13 grs 4759 & plain base 165 gr LFN bullet 

Main difference, 4759 is a stick powder. 4227 ball powder they throw different from measures. On target performance identical. 

Boats

Chuckster, magnum primers are needed to get the best results with 300mp. I think it is a no brainer on whether to go with 4227 or the 300mp. Not knocking 4227; used it for many years with great results. BUT, after seeing John L. test results with the 300mp and giving it a try, switched to the 300mp.
bob

My 300 MP loads all like Remington standard primers.  Others have said that they are a bit hotter than other brands.  In my 32-40 my groups tightened up considerably with 300 MP and Remington 9 1/2 primers compared to 4227 with any primer I tested.  A couple of months ago I did a primer test with my 28 G&H custom wildcat comparing Remington and Winchester standard primers.  The Winchester group was 3x the Remington one 

Jack

4227 May be small sticks never examined it carefully does measure well.

For no reason other than lot of shooters  used Pistol primers 32/40 & 38/55 that’s all I have ever used. One of my CPA rifles has 20,000 plus pistol primed cartridges through it with no visible wear. CPA adjustable hammer fall can be tuned to the primer.

Too late to change now have 3000 large Pistols on hand large rifle or any other primers not obtainable. It’s very possible original block can be harmed by pistol primers . Be interested others experience with LP primers. 

Boats

One of my 30-40 Krag cases trimmed down for large pistol primers. Like they say, nothing new under the sun. Pretty common practice for target shooters. The chambers in the rifles for this case are chambered short.  Case has a bazillion rounds fired. Primer pockets are getting perty loose.

The pistol primers were no advantage so I now use large rifle primers. Just cram them in a little harder.

Modifications to benchrest rifles is not an uncommon approch. They are made by competent folks for competent competitors who are also competent in knowing how they are to be used. These are also the same competent folks that these types of rifles are being sold to.