The H&R version of the Allin conversion had a two-piece extractor - actually screwed together instead of being made un one [pricey] forging. This led to the occasional 'unloading while going bang' syndrome as the extractor let go during ignition. H&R provided a fix in the USA, but I don't know how many made it here.
The Pedersoli version has a one piece unit, and I've never heard of any problems from that direction. By factory ammunition, do you mean modern jacketed ammuntion as used in the Ruger #1 or Marlin whatever it's called?
I most certainly do NOT advise using such fodder in ANY Trapdoor Springfield design. I don't shoot anything but lead in my Winchester High Wall - a much stronger action than the Allin breechloading design.
Remember that the original of this design entered service in 1873, with a black powder load of 70gr behind a 405g gr solid lead bullet. The maximum pressure load [SAAMI] for this BP cartridge is 25,000 psi. IOW, keep your loads in the region of this by using BP or any of the subs at around 60gr, or a suitably downloaded nitro load. Why so low? Well, trying to get 70gr of 3Fg into the modern case - AND the long bullet - is like trying to put toothpase back into the tube. I've been shooting .45-70 Govt (the correct nomenclature) for about fify years, and can advise you that trying to make the TDS shoot like a Marlin or Ruger #1 is fraught with disappointment, and possibly, danger. The TDS was NOT designed to shoot jacketed bullets of any kind, although low loads of nitro propellant that virtually duplicate the lower-side of the original loads are entirely possible.
Given that this is an informative subject, and that you probably have the same loading manuals as I do, be advised that up to 100m or so a good load is a .405gr flat nose lead bullet over 32gr of IMR4198. If you can finagle yourself a drop tube, then you just might get 60gr of Pyrodex RS or even 3Fg into the case, but you'll end up compressing the load somewhat. There are special dies that you can buy to help you do this consistently, but then a spare bullet seating die can do it just as well - I use 1/8th compression on a 50gr load and it works out just fine.
There is a LOT of advice on Youtube - Murpheysmuskets is good news.
Whatever it is that you do, PLEASE don't try and make it into something it never was - enjoy it for what it is - a piece of history.
You can see my High Wall in use by a pal's son on Youtube - tac's guns High Wall. You certainly know it's gone bang, but it's not going to blow you out of the back of the firing point on your ass with your legs in the air.
tac