300gr. bullets not grouping???

[VLP.204]

I cannot for the life of me get 300gr XTPs or MZs to shoot better than a 2 to 3" group @ 100yards. Ive tried AA5744 @ 44 and 45gr. I also tried N120 @ 57, 58, 59,and 60gr. I even tried waiting 10 min between shots in 50 degree temps. The funny thing is,all these different charges and the two different bullets shot all the same 2 to 3" group. I use a RW .33 vent liner, Warn bases (double checked to make sure screw was not too long) and QR rings, and a Leupold 2x7 scope. Could it be possible that my gun does not like 300gr bullets? I got some 250gr XTPs and MZs to try this weekend. Where is a good place to start with AA5744 and 250gr bullets?

 

[MCee67]

Try 42-43 grains first. My gun likes 44.0 exactly. A friend of mines MLII groups about 2.5 with 44... but his shoots great at 42!

 

[dwhunter]

Try some N110 with a 250 gr SST around 42 or 43 grs. :wink:

 

[sheephunterab]

It just could be you are pushing them a bit too fast. XTPs have never been the high-speed performers that the SST is....at least not in any of my guns.

 

[Trigger]

With the N120 start with 55 grains and work your way up.

 

[Grouse]

It just could be you are pushing them a bit too fast. XTPs have never been the high-speed performers that the SST is....at least not in any of my guns.

BINGO That is to fast in my guns. 40 or 42grns of 5744 is the ticket. 44grns is about a 2"group at 100yd.

 

[Anonymous]

Where is a good place to start with AA5744 and 250gr bullets?

39 or 40 grains-- I'm with Grouse on this one. :shock:

 

[snuffy]

My ML 10 likes the 250 xtps better than the 300s but noy by much. I shoot 44 grains of 5744 with the 250 xtps and get 3 shot groups with all holes touching. :wink:

 

[HighTechRedneck]

The only thing I have gotten my 10 II to throw the 300 grain XTP mags out there with the accuracy that you descride is 50 grn of RL 7. My original 10 ML is a different story. I can load almost any charge I want behind a 300 grain XTP mag and get 1 1/2" groups all day long.
Both rifles seem to like the 240 grain XTP mag much better than the 300 grain version, so if changing your load to what everyone reccomends does not work. Your rifle just might not like the 300 grain bullets.

 

[SW]

One of the original loads, 34gs 2400, with a 300XTP is extremely accurate in my gun.

 

[VLP.204]

I guess I will try 41, 42, and 43gr. of 5744 with 300gr. XTPs and MZs. What kind of velocity can I expect with these charges?

 

[Anonymous]

Going from memory, you will get 1900 - 2000 fps from 40 - 45 grains depending on your individual gun, primer, ventliner, sabot, etc. (45 gr. runs about 2025 fps in my 10ML-IIs).

Any time you get a 300 gr. bullet moving past 1900 fps, you have an extremely impressive load-- generous for any deer as far as you can accurately place a shot. Many deer have donated their lives to ballistic science showing just that.

Does anyone thing a .44 Mag can't take a deer cleanly? Take a peek at the hottest available .44 RemMag rounds for comparison, and you'll see that you are at a whole new level. :shock:

 

[Doohan]

VLP -

Have you tried changing out the vent liner or breech plug?

2"-3" groups no matter what you try usually mean a worn out ventliner.. How many shots do you have on yours and when was the last time the plug was cleaned?

 

[VLP.204]

Doohan, I made sure everything was tight, cleaned the breech plug and installed a new RW .33 vent liner.

 

[Doohan]

:huh?:

Ok, have you given the barrel a nice cleaning? Have you tried any other bullets? 250 XTP's?

You are not shooting XTP/MAG's are you ?? They will not group period...

What sabot are you using? With XTP's I use MMP short sabots..

With 250 class bullets and 5744 try 42, 43, 44 gr..

 

[VLP.204]

Well, I got out and was able to shoot two 3 shot groups. First group was 55gr. N120. Second group was 42 gr. AA5744. Both groups measured about 1-3/4" center to center @ 100yards. That should be good enough, as the season starts this Sat. Most shots are within 50 yards. Does anyone know the velocity of 55gr. N120 with a 300gr. bullet? I know that 42gr. AA5744 is about 1950 to 2000 f.p.s. They both shoot the same so I guess I will shoot the one with the higher velocity.