A Self-Invested Personal Pension (SIPP) is one vehicle many investors use to try and build wealth over the long term.

Given the timeframes involved, that can be a successful strategy. For example, over a 20-year timeframe, a compound annual growth rate (CAGR) of 3.6% would be enough to double the value of a SIPP.

That is not far off the current average FTSE 100 yield of 3.4%. Dividends could be boosted by share price growth, though of course falling share prices can negatively affect CAGR. On top of that, dividends are never guaranteed.

Still, as part of a diversified SIPP, I reckon there are plenty of shares to consider for investors who want to try and double the value of their SIPP over the long term.

Here are three of them.

British American Tobacco

For starters, British American Tobacco (LSE: BATS) offers an attractive yield of 6.5%. On top of that, it has grown its dividend annually for decades.

Whether it can continue to do so – or even just maintain the dividend – is a question investors need to consider seriously. Not only does the company have sizeable debt, but its core market of cigarettes continues to see weakening demand over the long term.

However, while there are clear risks, I also think this high-yield share has some clear attractions.

For starters, while cigarette sales volumes are in decline, they are still substantial. Cheap to make but expensive to buy, it is a highly profitable business space and thanks to its stable of premium brands, British American is able to charge premium prices.

Legal & General

Another FTSE 100 high-yield share for SIPP investors to consider is Legal & General (LSE: LGEN).

It aims to grow its dividend per share by 2% annually. That is smaller growth than before, but it is still growth. Even now, before any potential future increases, the yield stands at a juicy 8.5%.

With a large target market and established customer base, the financial services company can benefit from its strong brand as well as long market experience.

One risk I see is the sale of a large US business. That could be good for short-term cash generation but threatens to leave a hole in the profit and loss account in future years. Hopefully, growth in other areas might help Legal & General to fill that.

Bunzl

At a 3.2% yield, packaging supplier Bunzl (LSE: BNZL) does not match the 3.6% I mentioned in my example above. A 26% fall in the share price over the past year does not look promising either.

Over the coming decades, I am hopeful that the company can keep growing its dividend per share each year. I also see potential for the share price to rise.

Weak demand in key markets and elevated costs eating into profit margins remain risks. But Bunzl’s proven business model of acquiring businesses to build scope, economies of scale and become ever more attractive to global clients remains compelling in my view.

Clearly, management has work to do, starting with reversing a decline in revenues over the past couple of years. If it can right the ship, I think the current Bunzl share price looks like a potential bargain. I recently added some Bunzl shares to my SIPP.