How to decide what size pellet sizer is needed

tiptop

Member
Nov 12, 2016
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OH
JSB 10.34g has a head size of 4.48mm and skirt about 4.55mm. The sizers I'm considering come in six sizes: 4.48, 4.49, 4.50, 4.51, 4.52, and 4.53. The pellets would be used in a Gen 1 Marauder .177. .177" = 4.496mm but I don't know how exact the barrel ID is. I'm guessing I'd want to go with the 4.53 because anything smaller would compress the skirt quite a bit - but really I don't have a clue. Any advice? Thanks! 
 
First, my Gen1 Marauder (stock barrel) shot the 10.3 grain JSB Exacts nicely, setup for about 850 ft/sec.

Now, I'd say they typically come at 4.51- 4.53 (have not seen any at 4.48?) nominal, these days you may not see them sold in specific head size. The Air Arms pellets are also good, they have a thinner skirt. IMHO, the compression of the skirt is not nearly as significant as the head diameter, and I don't think you need to be concerned.

Try sorting the pellets by head size, and shooting test groups with the sorted pellets. You will likely see some opening of the groups (and POI shift) when you move plus or minus 0.02 mm from the nominally "best" size. For competition shooting, sorting can improve a score somewhat. If you are getting pellets with really high variance 0.03 mm or greater, you might find some difficulty with the entire tin. It does happen, even with good brands.


 
I've recently got one of these from TR Robb (UK) and it is not only adjustable but keeps the skirt a bit larger than the head which is desirable, it is cleverly made and works well. I have found that used in combination with a Pelletgage you can really work out what your barrel likes and replicate it:
http://www.trrobb.com/product/adjustable%20pellet%20sizer%20177

Hope that helps.
 
Asa, that's a nice tool. I am checking to see if they ship to Conus. I am getting serious about FT and my question is with this sizer, as an example. I am buying H&N FTT's in 4.50, 4.51, 4.52 etc all the same weight. Once I find which size my rifle likes using accuracy and chrono readings. From what I am reading you can set that tool to the size you want, am I correct on that Asa ?
 
"LIVIT"Once I find which size my rifle likes using accuracy and chrono readings. From what I am reading you can set that tool to the size you want, am I correct on that Asa ?


Yes that's correct. It doesn't have size markings though, it is a matter of adjust and measure - which is where the Pelletgage comes in useful, or quality calipers. 

The way this sizer is constructed seems to be that the main body has a chamber that diminishes in size from one end to the other with an adjustable stop at the narrow end. So you drop your unsized pellet in the wide end and push it to up to the stopper which resizes it and seeing as the chamber is wider at the tail end the skirt will always be wider. 

As you have probably worked out, setting the stopper further along by winding the the screw out that controls the stopper posistion will give you a smaller diameter on the head. When you have got to the desired size through trial and error you can use the locking nut to make sure the stopper position doesn't move, and then repeat...

In terms of getting back to previously used settings, the only way I have thought of to do this is to use calipers to measure the length of the screw and take of note of the reading that corresponds to each head size - there may be a smarter way.

Hope that makes sense.
 
Hey Matt, no I have not yet. Been working crazy 12 hr plus shifts at VA Hospital and I cant access those foreign sites on work pc. I am suppose to be off mon & tues , I will let you know then. I do know others have gotten them here and I think they do ship international. Apologize for not knowing more yet.... Dale


Update: He does ship to conus total price is $36.75
 
"LIVIT"Hey Matt, no I have not yet. Been working crazy 12 hr plus shifts at VA Hospital and I cant access those foreign sites on work pc. I am suppose to be off mon & tues , I will let you know then. I do know others have gotten them here and I think they do ship international. Apologize for not knowing more yet.... Dale


Update: He does ship to conus total price is $36.75
Dale, I greatly appreciate the info! Not a bad price at all, I think. I'm considering this with a digital caliper for measurement (less the $20 from amazon).

Best,

Matt
 
Matt, yw brother. I think its a reasonable price, considering what I have seen some similar items priced at, that are nothing more than a piece of plastic. I think this tool along with a pelletgauge, calipers and good digital scale is a must have, at least for me. Is that a Bull Dolphin in your avatar ? I have saltwater in my blood :) 

Zoey, I was wondering about a way to slug the gun without damaging pellet or taking apart my tuned rifle. I would think if you shot into the water at a bit of a distance it might work.