.20/13.73 Versus .177/13.43 MRD

[Franklink]

Recently had an old batch of .177/13.43 MRDs shoot well enough that I ordered some more.

Have shot most of a tin of the new batch and I'm not impressed.

This is 55 yards.
Tried them from 800 up to 915fps and getting the same results.

The above is in 18-20mph winds with gusts up to 32.

Also shot some last night around 9pm with h hardly any wind and also had larger-than-conditions groups.

You'll notice I broke out the measuring stick .20 gun to see if it was effects of the wind or if the .177s were really doing that poorly ....for my eyes the .20/13.73 group ain't bad-MUCH better than I can get with the .177/13.43 MRDs. Oh, the .20s are at 795-805.

Not to say the .20s are always better (different batches, different barrels, etc), but I choose the .20 in this comparison.

 

[Centercut]

But that's not possible... ALL pellets are the same and are NEVER the reason for poor performance!!!
Did you shoot the MRDs with a poly barrel? I've had good luck with regular barrels and .177 RDMs but I think the "old" Monsters with the truncated barrel body shoot better from Poly barrels...?

 

[Franklink]

Yep, .177 is a poly and the .20 is a 12 land and groove. Both guns are Veterans.

It's crazy how much variation there is from batch to batch and barrel to barrel. The more I shoot and the more guns I get to shoot the more I think that it's nearly impossible to arrive at any broad-brush-stroke conclusions.

 

[Centercut]

Yep, .177 is a poly and the .20 is a 12 land and groove. Both guns are Veterans.

It's crazy how much variation there is from batch to batch and barrel to barrel. The more I shoot and the more guns I get to shoot the more I think that it's nearly impossible to arrive at any broad-brush-stroke conclusions.

True, but finding good lots of pellets isn't "sorting" is it? My .22 Red Wolf HP was simply amazing with the older RDMs, but with the new ones I think my .22 Benjamin Marauder Semi Auto is more accurate. Must be the barrel, or maybe I'm not cleaning it after every 10-shot magazine. Who knows...?

 

[rash_powder]

I may be a bit behind - whats an MRD?

 

[Franklink]

I may be a bit behind - whats an MRD?

Sorry, JSB Monster ReDesigns.

In the case of .177, the MRDs weigh 13.43grains.

(.22 MRDs also exist, and they weigh 25.4grains).

In both cases (.22 and .177) the Original Monster had a straight walled waist between head and largest diameter of skirt and the RDs have a tapered mid-section. Also in both cases, the RDs have a slightly better BC than the Monster Originals, at least from most barrels.

 

[Ballisticboy]

I have not looked at the Monsters in detail, but one thing I have found with most of the heavier pellets is that in filling up much of the flare at the back to give the weight increase, the centre of gravity is moved towards the rear of the pellet, reducing the aerodynamic moments, and making the pellets potentially more sensitive to pellet barrel fit.

So any minute changes in dimensions from batch to batch may have a larger than expected effect on group sizes. This effect may be less obvious in barrels with lower twist rates.