Is this a Brunswick

Not a Brunswick persay, more of a home project at one time of different parts and pieces.

Basically, someone made or fitted a new set of rails to an old T-rail table.
They also took off & discarded any of the wood curtains that might have helped easily determine what model. Then they painted it black over any identifying veneer characteristics.

The legs (about all that can be usefully seen in your photo) suggest it *could* have been BBC.

Brunswick didn't really start making simple straight taper legs until the "Alexandria" in 1910 or 11. Same year, "St. Elmo" had simple square straight legs. Your's is not likely either of those because of some other obvious differences. I'm just putting an earliest date out there, if it is BBC.

Madison, as Trent suggested, came along about 1916 & had a long run into the 20's. The legs on Madison did not seem to taper, though. During the 20's, there were a number of tables with similar legs. If you can see any veneer patterns under the paint on the legs, it can ID the table.

By the end of the 20's & the start of the depression, this style of table was moribund. I think the Exhibition might have still been a T-rail? Not sure.

So based on the legs & making a good faith guess that it is BBC, it would have been made between 1911 & 1930.

Based on the slate, i didn't think they still made that type of wood inlay pocket shelf/cut-out after WW1 But I don't really know. I've seen (& own one) tables/slates from the mid 1920's & pocket cuts are completely in slate (no wood) by then.

I have worked on cabinets (wood parts of tables) and slate & made tools & parts for a table builder during the late 70's/80's. I am not a tech & have no set up experience.
I have heard some techs comment WTTE that T-rails can be made to play as well as anything; but might require tweaking a little more often.
When John switched from T-rail assembly of his tables, he said how much easier it was to build them bolted through (like GC) & how they stayed tight longer. YMMV
Or it could be like RKC said; & they found frame & legs one place, slates somewhere else, & made a set of rails to pull it all together.
You are the only one with eyes on it to report how successful the operation was.

smt

There is no way to run vertical rail bolts into rails designed as T rails, the slate only goes under the rails to the back of the feather strip, in front of the finish of the top rail. The only part of the rail sitting on the slate is 3/4" where the cloth is stapled to, that's all the footprint there is.

Correct, of course - you might have misunderstood what i was saying. He changed his patterns for ordering slate, & the whole build. Must have been thinking about it for years. Then one week decided & changed over.

John started building tables around 1960 IIUC. I believe he told me he originally sent off for plans from a magazine. Then had to study old tables in pool halls to figure out how to do it right. He was a good bit older than me. I think i told the story here.

One day sometime around 1979 or '80 i was in the local hardware store & this fireplug looking guy with a pack of luckies rolled up in his pristine white T-shirt barges in & comes straight at me pointing his finger. "You're Steve ...." he states jabbing me in the chest. The hardware store owner was taking my order and nods "yes". The luckies guy goes "i need to talk to you outside". I'm trying to recall if any daughters dads might have a beef with me & whether to duck out the back door instead of the front.

But he's pacing the sidewalk out front & there's at least a local cop car not too far up the street. I go out cautiously & he comes at me again. "I heard you can make anything out of wood".

I kind of said something like "that's a lie or at least an exaggeration." But he needed some curved bar rail mouldings made & couldn't (at that time) find anyone to make big mouldings, or to match mouldings, especially with curves, & it just went on from there. After figuring it out, realized i had heard of him because he set up all the local tables in a wide area and traveled a lot further at times on request. He dealt tables, & also built a few tables from scratch every year. At first built to order, later he'd make them on spec as well. He later added dealing import woodworking equipment when it first started to hit the docks in Baltimore.

Anyway, I made whatever John wanted, including simple oddball tools. I don't even remember most of the stuff. I did not know how tables were built, & it is a great regret that i didn't really care at the time nor pay much attention. But it does stand out in my mind that one day he asked me over to the shop & showed how he had ordered some slates with wider margins & was going to start drilling straight up through from the bottom, to hold the rails on flat. I honestly did not know how he had been doing it before. But it was clear that this was supposed to be a come-to-Jesus moment so i nodded along. He was pretty wound up & told me it was the method Brunswick used.

John used to drive his Ford van up to the quarries in PA once or rarely twice a year. He apparently sometimes built one-piece 7 & 8 ft tables before i knew him. Being a kid, i figured he was over the hill at 40-something & all those luckies were slowing him down; but he explained that he could level a 3pc just as well, sometimes better on 8ft tables. When I knew him, we only got 3pc sets, 3 sets at a time in the van. I believe John might have built a few 9 ft by special request; but most residential wanted 8 ft. I never saw any being built bigger. I have to add, the tables i saw that John had built that i liked the best, just the slender, classic, esthetic lines, i later learned were T rails. I never heard the term then & would not have understood what it meant. Figured all that out when i got back into pool again a few years ago after eye surgery when i couldn't do much else for 6 months.

Sorry.
Started thinking about John, & it's hard to convey what a solid remarkable guy he was. Pool was not even his day job, but it was his life.

smt