so far my Huntsville hasn't had a wandering pin, but round count only >500.  as an aside, if i do have the issue, i'm tempted to put it back in with red loctite and see if that keeps it in place.  and if i never have the problem, so much the better.  until more R51s get over the 1000 rd. number this issue will be hard to judge as a design oversight or an anomaly.
good luck with the repair from Remington.
-tdbru

MR220V is right.   with the R51's light weight and short sight radius, and the relatively heavy trigger pull, one really has to focus on the front sight as you shoot.

i tried shooting at 25 yards but to get the impact anywhere close to center of the target, i had to cover so much of the target that it disappeared and i lost all sighting reference.  i didn't shoot very well. 

i don't like these "combat" sights at all.  i'm going to look for a shorter front sight.

as Col. Whelen said, " only accurate rifles are interesting".  well that applies to pistols too.  and these sights make accurate aiming, for me, impossible.  when you can't see your target in relation to the sights, you have nothing to aim at.

otherwise, another box of ammo today at 25 yards.  mix of 115 and 124.  no issues with functionality.
tdbru

besides the mags that came with my R51 (gen 2 mags), i picked up some more from brownells.  they came in  the remington blister packs.  they were gen2 mags.  as posted by previous contributors, i filled the magazines and emptied them several times before putting them into service.  if i make sure that the mag is fully seated, i have no issues.  sometimes i push the mag in and hear a click and think the mag is fully seated but in actuality it wasn't.  so now i try to have a finger or a thumb on the mag release button lightly as i push the magazine home.  once i feel the mag release button pop or snap i know the mag is latched and then i have had no issues with the magazines.  they simply function.
-tdbru 

put another box of winchester 124gr NATO though it today.  no hiccups.  with (very) slow aimed fire kept 95% of the box in a 2" circle at 7 yards.  still learning to shoot it.  weighed it with 8 in it and scaled at 26 oz.  still don't like the "combat" sight picture you have to hold, but i'm (slowly) learning.

so that puts it at >400 now.  just getting it broken in 
tdbru

this from Remington:

Remington Support
Service Ticket Response

Good morning,

  The front sight will be a 1/16" Allen head size and the rear sight is a 5/64" Allen head size

and i did confirm those sizes of allen wrenches seem to fit my R51 sights.  the rear seems to have a bit more play than the front, so perhaps my 5/64" allen wrench might be just a wee tad undersize?  but i'm sure it will work.

i could also fit a 2mm(?) metric allen wrench in the rear sight set screw.  and it seems to fit a tiny bit tighter than the 5/64".
tdbru

Pat Riot,
any time you can get to the range and shoot it's a good thing.  so of course a retest is in order 
all my mags are the gen2 variety and i am not having issues with any of them, other than they don't like the bullet profile i guess for nosler defense.  everything else i've put through it has been a non-issue.  it just works.
tdbru

Got to the range again.  Ran 8 more mags of ammo through.  with 3 new mags.  124gr. ball, quite a variety of SD HPs.  some reloads. 

this time over sandbags at 25 yards and a chronograph. 

Win and Rem come closer to published +P velocity in 124gr. (1200 fps) by a long shot compared to Hornady and Nosler.

Win PDX1 124gr. +P was around 1130fps
Rem 124gr +P golden saber was around 1125fps.
Hornady 124gr +P american gunner with xtp was around 1080fps
Nosler 124gr. +P bonded HP around 1020fps. 

hornady and nosler need to take lessons from Remington and Winchester on how to load to spec velocity.  Win and Nosler claimed 1200 fps. 
Hornady claimed 1175fps.
nothing on the box of Rem golden saber.

Win 124gr. NATO was also around 1130fps with a published mv of 1200. 

my R51 didn't like the nosler defense 124gr +P bonded JHP.   nosedived on the 2nd round after the 1st shot and jammed.  they also shot quite a bit lower and were quite scattered.  i wasn't impressed with the nosler defense ammo.

the rest grouped respectably and all around the same POI.

the black was 6 1/4 inch diameter.  i was holding the top of the front blade even with the middle of the bull.  so the bullets grouped below this.  none the less, 80% were in the black with 20% below in the white.  had i held "combat" sights the % in the black might have been higher.   but i could be more precise with aiming with this hold.  i was trying to get a feeling of how it grouped mostly.

i notice that it is not easy for me to shoot this well.  probably short sight radius coupled with relatively heavy trigger pull.  that just means i need to practice some more.

still happy with this R51.  but it is not as easy for me to shoot tight groups with this as it is with a full size service auto.  but that's to be expected i suppose.

tdbru

if anyone has installed the trijicon sight set, did you observe a POI shift with the new sights?  if so, which way?
thanks,
Brian

sorry about the long winded post. 
tdbru

picked up an R51 a couple of weeks ago.  Huntsville S/N.  read owners manual.  disassembled.  cleaned.  lubed parts.  reassembled.  yes, reassembly was difficult the first time.  i've done it 3x now and it's much easier.

took to range.  loaded mag.  chambered round.  no bang.  tried several times.  no firing pin marks on primers at all on any of the rounds in the magazine.  go home.  field strip pistol.  firing pin is really hard to move in breech block with fingers.  take pliers in leatherman wave and grip tail of firing pin.  push back and forth in breech block with a lot of effort.  i am thinking some manufacturing debris maybe didn't get removed??  drive firing pin retaining cross pin out of breech block and use pliers to take firing pin out.  examine firing pin.  the cylindrical section of the firing pin has a slot milled in it for the cross pin to retain firing pin in breech block.  at rear of the milled slot there was a raised hump of metal that stuck up.  the top had the finish rubbed off of it.  evidently this firing pin wasn't caught by any kind of QC.  took out the file on the leatherman wave and filed the hump down to match the cylinder body.  reinstalled the firing pin.  reassembled the pistol.  ran like a champ after that.  no FTF, FTE, FTF, etc.  tried over 300 rounds of 115gr. fmj RN and FP, 124gr. RN NATO, 124gr. RN standard, 124gr. HP - 2 kinds - both +P, 147gr. fp - 2 brands.  125 Hornady HAP reloads.  everything worked.  both magazines.  2 hand hold at 7 yards kept magazine full in a 2" circle.  mine is "combat" sighted, not bullseye sighted.  so i had to cover the target to keep rounds in the bullseye.  not conducive to tight groups for me.  tomorrow i'll try over sandbags if i get the chance.  emailed Remington and asked for a new firing pin as this one had the protective finish removed where the hump got ground down (parkerizing??) and i wanted a good firing pin to put back in that didn't have any finish removed.  just got it in the mail today and installed it.  while i was doing that i examined the pistol for wear.  saw very little.  the ramps in the breech bolt body that the slide engages to lift the bolt out of lock showed some burnishing.  to be expected in my mind.  also the frame ledge where the bolt locks up at firing showed some anodizing wear, but no dimensional changes that i could tell.  the first time i disassembled the R51 when i got it i noted that the barrel feed ramp came polished from the factory and that wasn't something i'd need to do on this one.  all interior surfaces of the slide were nicely machined and finished.  no burrs found.  barrel interior finish was very good, in my opinion.  no other issues.  just the firing pin issue.  fit and finish are very nice in my opinion.  accuracy is good but the short sight radius makes it a bit tougher as compared to a pistol with a longer sight radius.  trigger feel is acceptable in my opinion, not great, but better than some i've tried.  reset isn't very noticeable to me unless i really concentrate on it.  not an issue for my use however. not too keen about the plastic trigger, but, don't even notice it in use and so as long as it doesn't fail in any way, it's a don't care functionally. aesthetically i think it would be nicer, to me, being anodized aluminum with no side to side wobble, but who knows, that might wear faster than what is in there now.  but it would look nicer in my opinion.  recoil is easily tolerable, barrel flip seems minimal.  feel in hand is good.  weight is nice for carry.  quite a bit lighter than any full size service auto.  grip safety on my instance clicked on and off audibly as well as being very tactile.   i like the fact that there are no other safeties other than the grip safety.  grip angle is quite comfortable for me.  i have larger hands so this fits me so much better than a SIG 938 i tried.  the grip length on the R51 is good for my size of hand.  trigger reach was no problem.  magazine release is difficult without changing grip as the recessed magazine release buttons, at least on my instance, take a deliberate strong vertical actuation which i cannot accomplish with either a thumb or finger without changing grip entirely.  maybe that will loosen up with use?  both magazines drop free, though, when i finally am able to fully depress the magazine release button.    i did have a nose dive in the magazine when i failed to get it fully seated into the magazine well and the magazine dropped slightly.  that was operator error.  both magazines by the way have the gen2 hump  at the front of the follower.  once i fully seated the magazine until it clicked the magazine latch, then there were no more nosedive issues.  other than the firing pin issue, which Remington did a great job of sending a replacement part right away, i've had no issues with this copy of the R51 gen 2.  a friend picked up 2 of them and has had no issue with either of them, other than difficulty in field stripping and reassembly.  i like this one enough i might have to pick up another one.  i am looking forward to shooting over a sandbag rest and see just what size groups it can deliver with me driving.  myself particularly i don't care for the "combat" sight picture this R51 seems to be setup for.  i prefer more of a bulleye setup where the bullet impact is at the top of or just over the front sight.  personal preference i guess.  i noted that the 115s grouped a bit higher than the 124s which grouped higher than the 147s for the same sight picture.  in fact i had to really cover the target a lot to get the 147s to shoot to the center of the bullseye.  standard 124s and +P 124s didn't seem to have much difference in recoil to me.  both i could hold in the 2" target center at 7 yards offhand for a full magazine each.  i am still getting use to the trigger and short sight radius.  and i am not a great shot with a pistol anyway.  but i am pleased with this one.  i picked up a galco stinger holster for it and the R51 fits in that holster well and the whole rig carries comfortably.  i rarely noticed it was along for the ride.  i'll be taking it with when out hiking, hunting, camping, etc.   i like target shooting anyway, but i am finding this R51 is a hoot to plink with.  i am glad i got it.  i have decided that due to the effort to field strip and reassemble, i will simply use a q-tip to swab out the carbon accumulation from the pistol with the slide open, and then run a boresnake through the barrel a couple of times and call it good for the most part.  maybe field strip and clean once a year?  i really like the low bore axis too.  the low bore axis is really noticeable when compared to full size browning type tilt barrel actuating service pistols.  and though looks are good or bad based upon individual preferences, i really like the looks of the R51 too.  since i quickly decided this one is a keeper i ordered a few more magazines to go with it.  my only change that i am going to make is to go to tritium night sight set.  i just can't decide on which ones yet, though i'm leaning towards trijicon personally.   i am looking at the manufactures sight heights to see if i can find a set with a bit more height difference between the front and back, so that it shoots more towards a bullseye sight picture rather than a combat sight picture, though that is simply a personal preference by me.  compared to a full size service pistol, this one carries much more nicely.  it'll be the one i have with when i'm not specifically headed to the range for some target shooting, though it will go with to that too.  the full size service auto is fun to shoot, but they are big enough and heavy enough that i usually won't strap it on when out hiking, camping, hunting, etc. due to the extra weight primarily, and bulk too.  this R51 will be going along now.   as i mentioned i hope to get to the range tomorrow to test the groups over sandbags, and try to get some chronographing done as well.  This is my 2 week report.  Looking forward to putting many more rounds downrange with this R51.
regards,
tdbru

picked up an R51 2 weeks ago.  really like it.  been hunting and target shooting many many years.  have done handgun hunting.  lots of plinking.  tried metallic silhouette with a 357 once.  prefer S&W revolvers, but this little R51 is growing on me.  i'll post more details of the R51 in the discussion forum.
tdbru