I took my Knight DISC .50 out last weekend and for some reason it just wouldn' t group very well. The load I was using is 100gr. 2F T7 with a 215gr .40cal PR QT sabot bullet. I' ve just switched over to these slightly lighter bullets from the 235gr .40cal QT' s at the beginning of the year because the 235' s overpenetrated the deer I shot last season and according to the PR website the lighter bullet will expand faster than the heavier version.

Anyway, as I walked downrange to check my target I started picking up the spent sabots and noticed that at least 75% of them had one or more petals damaged or broken off. Only a few looked like they had opened evenly and were still completely intact.

What I' m observing on the target is I' ll have two to three shots in a " group" within 2-3" of each other, then two or more flyers that are as far as 8" out of the group. Bearing in mind that I' m shooting off of sandbags with a 4X scope, I KNOW that it is not me that is the cause of this, as I was being very careful when shooting these groups because of this inconsistancy, and because I took my scoped 10/22 out and shot a nice 3" 10-shot group to test myself.

So I' m wondering what, if anything, effect on accuracy the broken sabots might have? I' m also wondering what the typical symptoms of a damaged scope might be? The scope is a 4X Simmons shotgun scope that I' ve had for three years, and that' s seen no real mishandling " abuse" , but has been subjected to several hundred muzzleloader recoil shocks.

Thanks,

Mike

Just a guess as I' m not much into sabots, but it sounds like you might be pushing them a little too hard. I would thoroughly clean and de-plastic the barrel and either drop the charge a little or add a buffer between the powder and sabot. I' m told a 28 gauge shotcup cut off at the top of the thick base works wonders.

The other thing is temperature. How hot was it and how long did you wait between shots?

Toby Bridges over at hpmuzzleloading.com has recently done some reporting on hot weather shooting that you mind find interesting/helpful.

I would say it is definately the sabots. My guess is that you are using the sabots that come with the PR QT bullets. If I am not mistaken these are Harvester sabots. Havester sabots, from my experiences, are much softer than MMP sabots, and will not hold up as well to higher pressures, velocities, and heat as well as the MMPS sabots. You may want to give MMP hi pressure or Hornady (made by MMP) hi velocity sabots a try.

As the temps outside climb into the upper 80' s and 90' s, any sabot tends to become soft and pliable. Ramming them home in a hot barrel doesn' t help them any either. Let your barrel cool (as much as possible) a few minutes between shots, take it off them bench top and direct sun light, and place in in the shade for a few minutes. Also, to help keep my sabots in a semi cool and much tougher state and ready to shoot, I carry a small beverage cooler with me to the range. In this small cooler I keep a couple froozen blue ice packs and I place my sabots and bullets on top of the ice packs. This keeps them cool and tough for good accurate shooting.

Yes, they are the blue sabots that come with the QT' s. I also wonder if it mught be because of the thickness of the petals (roughly .05" ) being so great and without any relief built into the base to allow them to flex. The sabots are always broken right at the base of the petal where it meets the cup.

At this point I' m considering removing the scope and going back to 385gr Great Plains conicals. In my area shots are rarily >75 yards, and 100 yards max. I' ve been toying with lightweight sabots because I' ve been trying to turn the gun into what it' s not, a flatshooting centerfire rifle-like performer. Comparing the accuracy and terminal performance in deer, I' m starting to realize that a big heavy conical is the ticket for short range take down power.

Mike

try a different type ; or try power-belts and see what happens.
power-belts work great for me.they might be the answer ; who knows?????????
just a thought !!!

driftrider..............

Without a doubt - you are overpowering the sabots! I' ll bet a dollar to a donut that if you drop your powder charge to the 80 to 90gr range, you' ll find much improved accuracy - plus.........you' ll improve the bullet' s expansion.

Think about it..............if you drive a smaller bullet at a faster rate (due to it' s lighter weight) it' s not going to have the TIME to expand before it passes through the carcass (i.e. a military .223 vs. a 7.62 cal round).

I shoot the 300gr Qts in my Knight USAK with 80gr of 2fg 777 and I can cover a 3-shot group with a penny at 50meters and it will knock down anything short of an elk. BTW....the sabots with this load don' t break off - but the petals are " helicoptered" out at 90 degree angles - any more pressure and I' m sure they will rip apart.

Overclocked makes a very good point about cleaning. Pushed that hard - you will have plastic fouling in the barrel. Scrubb it WELL with a bronze brush and I would advise either hitting it good with CVAs Advanced sabot cleaner or a round or two of a J-Bs-type bore paste to remove it all.

1 Shot -
I was under the impression that all of PRBullets sabots were MMP sabots. I know all of the larger bullets (300gr & up) sure seem to be. MMP does make colored sabots as well for the different calibers - but for these lighter bullets, they may not be the heavy-duty, High-pressure ones (which would account for driftrider' s problems).

Mark,

What you mention about all of the sabot petals opening up evenly at 90 degrees, that' s what I' m looking for, too. Mine seem to be bent back so much that they break off. Maybe I am driving them too hard. I don' t have a chrony, so I don' t know how fast the bullet and sabot are leaving the muzzle with the 100 grain charge. I guess I figured that the lighter bullet would need the greater velocity to get the energy and penetration that the heavy bullets have by virtue of their weight. I' ve never noticed any excessive plastic fouling in the bore. I spit patch between every shot and brush the bore about every 5 shots or so. I quess I also figured that since PR lists their ballistics data with heavy fast " magnum(b)" loads (150 grains of Pyrodex), that they should be able to handle 100grains of 777. Maybe I' m just overestimating the capabilities of the sabots.

Anyway, I' ve removed the scope from my ML and I' m going to just use the iron sights from now on. I' m also going to go back to heavy conicals again as I' m starting to think that small, light fast bullets aren' t the ML' s forte. The deer I shot last season ran 250 yards, through a creekbed and back up the other side, with a through-n-through hit from a QT that decimated one lung and the back part of the heart. The year before I hit a much larger deer with a 460gr Great Plains conical in the exact same place, but the bullet didn' t go all the way through, but rather bounced around inside doing some incredible damage. That deer didn' t get 6' , and I think she only made it that far by virture of the impact of the slug.

I think that ML' s are just more efficient with heavier projectiles.

Mike

driftrider... I agree with your concept of using big, heavy bullets for hunting.
All my ML hunting has been done with 350gr or heavier bullets and I' ve never had to track an animal yet. (plus the heavy bullets shoot better for me anyway)

I can really suggest the PR 350gr QTs or Extreme HPs. These have flat out lifted rams & boars off of their feet for me with a 90gr 777 load. One such QT I extracted had more than 100% expansion in the body cavity (.45cal bullet mushroomed to a full inch in dia.). I am more comfortable using these over conicals as they give me better accuracy and less chance of the bullet working itself off of the powder during a stalk or climb up a tree.

I also have some 400gr Extremes from PR ...................... pushed with 100gr of 3fg 777 - I think they would take the top off of a battleship! [] (you should see the size of hole it put in a Corsican Ram [:-] )

I think I found the problems...

I took my ML to the range today and fired a total of 40 rounds trying to get it to shoot the way I wanted it to. To test the scope problem theory I shot about 15 rounds to get it zeroed with the heavier bullets and to shoot a few groups. I did this with 460gr Hornady conicals. The resulting groups were terrible. Most were 6" + at 100 yards, mostly because the point of impact seemed to shift midway through the string. So, out of frustration, I removed the scope right there and decided to just shoot it the old fashioned way, with the iron sights. Well after a few rounds to get it sighted in I proceeded to shoot 10 shots into a 5" circle at 100 yards. Not bad for iron sights. All then shots would have been kill shots on a deer, so I' m not complaining. Seems as though the inexpensive Simmons shotgun scope just wasn' t able to hack a few hundred muzzleloader recoils and finally went t*ts-up.

After I confirmed that I could still shoot a decent group sans scope I decided to retest the 215gr. .40 QT sabots. The change was that I was shooting 100gr (2 pellets) of Pyrodex instead of 777. I shot 20 of them and not a single shot was more than 6" from the center of the bull. Recovering some of the sabots revealed that they were intact and had opened nicely. According to the data, this load would put the muzzle velocity probably in the 1700-1800 range, which isn' t bad at all. I also noted just how much easier shot to shot reloads were with the Pyrodex compared to the T7. I found that I had no need to swab between shots, which is necessary with T7. In fact, I found that swabbing the bore would cause the next shot to be a flyer most of the time. There is also much less blowback into the action as well. I can' t help but wonder just now much more pressure is being created with T7. Since this is the first time I' ve shot Pyrodex again after shooting the T7 for so long I think I' m convinced that Pyrodex, all things considered, is a superior propellant to T7, at least for me.

And since I have two pounds of it that I bought before switching to T7 I' m all set for powder for awhile too!

Thanks for the help guys.

Mike

Driftrider, Glad you found the problem.Cheap scopes are a major factor in inconsitent groups,and most people just don' t realize they have a bad scope.If you ask me your scope is the most important part of any rifle set up.The cheap name brand scopes can' t handle recoil well at all and will usually fail.Also intresting comments on the 777 powder.Good shooting[]